ABSTRACTS from the 5th International Crustacean Congress

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Aguzzi, J. and Abelló, P

Insituto de Ciencias del Mar-CSIC, Barcelona, Spain

Activity rhythms of Nephrops norvegicus (Crustacea: Decapoda: Nephropidae) from a continental slope population in the western Mediterranean Sea based on time-lapse video recordings

Infrared time-lapse video recording has been used to survey the locomotor activity behaviour of freshly-collected Norway lobsters, Nephrops norvegicus, kept in the laboratory in constant conditions of temperature (14°C) and darkness during 5-7 days. The individuals used in the experiments were freshly collected by trawling on muddy bottoms off-shore Barcelona (western Mediterranean) at depths of around 450 m. A total of 17 adult males has been analysed. Most of the activity took place during the expected night-time. Several peaks of activity were often recorded within the main night activity period. Time series analysis (periodogram) has allowed detailing the precise periodicity shown by each individual. Multivariate analysis has allowed detecting similarities among individual activity rhythms based in the resemblance of the estimate forms.

Ahyong, S.T.¹ and Schram, F.R.²

¹Dept. of Marine Invertebrates, Australian Museum, 6 College St., Sydney, NSW 2010 ²Institute for Systematics and Population Biology, University of Amsterdam, PO Box 94766, NL-1090 GT Amsterdam, The Netherlands

The phylogeny of the reptant Decapoda

The high level phylogeny of the reptant decapods has been subject to much debate for more than 100 years. Not only have the relationships between decapod infraorders been disputed, but also their monophyly. Previous approaches to investigating reptant phylogeny have largely followed 'traditional intuitive' methods whilst cladistic methods have been applied to reptants only in the last decade. The present study investigates reptant relationships using cladistic analysis of morphological data. The phylogenetic position of the glypheoids, known only from fossils or the extant Neoglyphea inopinata, and enoplometopids with the single extant genus Enoplometopus, are currently controversial among carcinologists. Our present results are well resolved indicating the positions of each of the major reptant groups.

Almeida, M.J. and Queiroga, H.

Departmento de Biologia, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal

Factors that control recruitment of Carcinus maenas megalopae to an estuary (Ria de Aveiro) on the Portuguese west coast

We studied daily settlement of Carcinus maenas megalopae in the Ria de Aveiro during three months, using standard artificial settlement substrates. We identified two settlement peaks that could be related to wind forcing of shelf circulation in an oceanic eastern boundary: increasing northward component of daily wind stress was positively associated with recruitment episodes, at time lags of 1 and 6 d (p<0.005). We did not find any relation between tidal range or subtidal sea level and the input of megalopae to the estuary. Compared with decapod species from other systems, megalopae abundance in the collectors was low (daily average of 0.18 ind./collector). Given the high density of the species adult population in the Ria de Aveiro, it appears that maintenance of the population is achieved in a background of low supply of megalopae. This would imply that density-dependent post-settlement processes are less important than supply of larvae for the dynamics of the population.

Alvarez, F., Villalobos J.L. and Acuña P.

Colección Nacional de Crustáceos, Instituto de Biología, Universidad Nacional Autónoma de México, Apartado Postal 70 - 153, México 04510, D.F., México

Populations of the genus Macrobrachium with abbreviated development from Mexico: how many species are there?

With the recent discovery of 12 populations of freshwater prawns of the genus Macrobrachium with abbreviated development in southeastern Mexico, new taxonomic challenges have emerged. These populations are characterized by: small sized adults of around 6 cm of total length, small distribution areas covering a few hundred meters along a river, and the production of up to 20 large eggs from which larvae with different degrees of development hatch. The external morphology across populations is very uniform, the rostrum and second pereiopods do not offer enough characters to identify each population reliably. Two new species have been described belonging to this complex, however, the question arises of how many species are there? Three different approaches were used to compare three populations: enzime electrophoresis, adult morphometry, and larval characters. The results indicate that all the populations represent different species, a situation that could potentially double the species of Macrobrachium in Mexico.

Andersen, L.E.¹, Norton, J.H.², Levy, N.H.² and Storey, A.W.³

¹Centre of Environmental Management, University of Central Queensland, Gladstone, Queensland 4680 ²Queensland Department of Primary Industries, Oonoonba Veterinary Laboratory, Townsville, Queensland 4810 ³Zoology Department, University of Western Australia, Crawley, Western Australia 6009

Metal burdens, shell disease and immune responses in the mud crab Scylla serrata from Port Curtis, Queensland

In 1994 a previously unrecorded rust spot shell disease was observed in mud crabs (Scylla serrata - Forskal) from Gladstone (Port Curtis Harbour), Central Queensland, Australia. Rust spot lesions appear to be caused by a defect in the formation of the endocuticular layer, rather than as a result of the pathogenic cuticular degeneration observed in classic shell disease. The hepatopancreas from 105 mud crabs from both Gladstone and Ayr (control site) have been analysed for a complement of 57 different metals over two consecutive years. Although generally there was no significant difference between metal levels in the diseased compared to the non-diseased group from Gladstone, levels of Copper and Zinc were shown to be elevated in Gladstone compared to Ayr in both 1999 and 2000. Results also indicate elevated metal burdens in Gladstone crabs compared to Ayr. Higher within-group variation in metal levels of the diseased female crabs from Gladstone compared to the other groups suggest that the diseased crabs may be unable to regulate metal levels. Measures of haemolymph immune factors of the same crabs also suggest an elevated immune response from the Gladstone crabs compared to controls. The relationship between the elevated immune response, metal levels and shell disease is being further investigated.

Anger, Klaus

Biologische Anstalt Helgoland; Stiftung Alfred-Wegener-Institut für Polar- und Meeresforschung, D-27498 Helgoland, Germany

Salinity as a key parameter in the larval biology of decapod crustaceans

Salinity is an ecological key factor in the life of estuarine and coastal plankton, and hence, also in the biology of meroplanktonic decapod crustacean larvae. Its influence has been noted in larval survival, development, morphology, the moulting cycle, growth, feeding, metabolism, energy partitioning, and behaviour. In this review, detrimental effects of unfavourable salinities are shown with examples from all these principal aspects of larval biology. Consequences of osmotic stress are discussed in relation to interacting effects of other environmental variables such as temperature or toxic pollutants, and in relation to intrinsic phenomena associated with development, the moulting cycle, and endocrine control systems. Special adaptations to variation in salinity are demonstrated in the reproductive strategies of estuarine species, in larval behaviour, and in the ontogeny of osmoregulatory structures and functions. Putative relationships between osmoregulatory patterns and the metabolic response to salinity are proposed.

Anker A.

Muséum National d'Histoire Naturelle, 55, rue de Buffon, 75005 Paris, France

Phylogeny of Alpheidae (Decapoda, Caridea) - preliminary results of a cladistic analysis of morphological characters, with particular emphasis on evolution of snapping claw

A cladistic analysis of Alpheidae, using the conventional PAUP methodology, produced a majority rule consensus tree which is the preliminary phylogenetic hypothesis of generic relationships within Alpheidae. The monophyly of the family is supported by several features, however, its affinities to other caridean families remain rather obscure. Relationships of two problematic genera, Yagerocaris and Pterocaris, are discussed in in light of the phylogenetic results. Evolution of robust, usually asymmetrical, first chelipeds is particularly complex. Notable modifications and polymorphism of chelae occur even within some " lower genera ". Plasticity of chelipeds is important in both lower and higher genera. As the monophyly of the clade uniting five genera all characterized by the snapping mechanism is reasonably supported (Synalpheus appearing as a sister group to the other four genera, including Alpheus), a unique origin of the snapping mechanism in Alpheidae should be assumed. However, Coutière (1899) believed that the snapping claw evolved independently in Alpheus and in Synalpheus.

Anker A.¹ and Jeng M.S.²

¹Muséum National d'Histoire Naturelle, 55, rue de Buffon, 75005 Paris, France ²Institute of Zoology, Academia Sinica, Taipei, Taiwan 115, R.O.C.

Cryptic species and colour patterns in Alpheidae (Decapoda, Caridea), with particular emphasis on goby-associated species of Alpheus.

Despite numerous taxonomic studies in the family Alpheidae all larger alpheid genera remain more or less problematical in this respect. Misidentifications or incomplete identifications are frequent. There are multiple reasons for this situation : presence of numerous cryptic / sibling species, absence of original type-material, superficial diagnoses, descriptions based on incomplete specimens, questionnable synonymies, rarity of specimens, insufficient or lacking field data (incl. colour patterns). Several common, " well defined " and " widely distributed " taxa actually represent species complexes, making the identifications of specimens very difficult or impossible. Numerous studies of ecological and behavioural aspects of associations between gobies and Alpheus spp. were not paralleled by taxonomic revisions of A. brevirostris species group, which contains the majority of goby-associated species. Detailed examinations of numerous UW photographs show that each species could be more easily identified by its distinctive colour pattern, however, most colour patterns can not yet be matched with descriptions based on morphology.

Anker A.¹ and Jeng M.S.²

¹Muséum National d'Histoire Naturelle, 55, rue de Buffon, 75005 Paris, France ²Institute of Zoology, Academia Sinica, Taipei, Taiwan 115, R.O.C.

Symbioses among the Alpheidae (Decapoda, Caridea)

The shrimp family Alpheidae is one of the largest decapod groups, and is particularly representative and diversified in shallow tropical waters. A considerable number of species is associated with other marine organisms. Alpheid shrimps are actually second in number and diversity of associations after the palaemonid subfamily Pontoniinae. All known symbiotic alpheids and their associates have been compiled in a huge reference table. The most interesting examples of these associations are presented in order of their ecological / behavioural characteristics. The hosts and associates of Alpheidae include species from ecologically and phylogenetically very different phyla, such as Porifera, Cnidaria, Annelida, Echiurida, Mollusca, Echinodermata, Urochordata, Crustacea and Pisces. This fact can be explained by the obviously high adaptative potential of Alpheidae, which may be partly due to their morphological variability and plasticity (e.g. first chelipeds, dactyli of third to fifth pereiopods) and to their strictly benthic life-style.

Asakura, A.

Zoology Department, Natural History Museum and Institute, Chiba, Japan

A taxonomic review of the hermit crab of Diogenes with the simple rostral process from the Japanese and adjacent waters (Decapoda: Anomura: Diogenidae)

The genus Diogenes is widely distributed in temperate and tropical waters of the world. The genus is divided into two groups. The species of Group I (sensu Rahayu and Forest) are those with well developed antennas, in which the antennal peduncles overreach the ocular peduncles; the species of Group II have only poorly developed antennas with the antennal peduncles shorter than the ocular peduncles. In this presentation, I review the species with the simple rostral process in the Group I from the Japanese and adjacent waters. These include D. costatus, D. dorotheae, D. edwardsii, D. goniochirus, D. guttatus, D. nitidimanus, D. penicillatus, D. rectimanus, D. spinifrons, and some undescribed species.

Auel, H.

Marine Zoology (FB 2), University of Bremen, Bremen, Germany

Trophodynamics and ecological role of the Arctic pelagic amphipod Themisto libellula.

Hyperiid amphipods of the genus Themisto play a key role in pelagic ecosystems. They prey on mesozooplankton and are major food items for higher trophic levels. The abundance, biomass, population structure, respiration and ingestion rates of the Arctic Themisto libellula were studied in the marginal ice zone of Fram Strait between Greenland and Svalbard. Abundance of T. libellula ranged from 0.02 to 0.05 ind. m-3. Juveniles of 10 to 20 mm total body length dominated throughout the investigation area. Males reached sexual maturity at a body length of >21 mm, presumably in their third year. Ingestion rates measured 0.019±0.015 d^–1 and 0.019±0.006 d^–1 according to feeding experiments and an energy budget approach based on respiration rates, respectively. The predation impact was low when compared to the mesozooplankton standing stock. Nevertheless, T. libellula may consume a substantial portion of zooplankton secondary production, since P/B ratios are very low under Arctic conditions.

Auel, H.¹ and Werner, I.²

¹Marine Zoology (FB 2), University of Bremen, Bremen, Germany ²Institute for Polar Ecology, University of Kiel, Kiel, Germany

Amphipods beneath the Arctic pack ice - adaptations to a sympagic versus a pelagic life style

The feeding behaviour and energetic demands of carnivorous Arctic amphipods were investigated off Greenland. Studies included the sympagic Gammarus wilkitzkii and the pelagic Themisto libellula occurring beneath the pack-ice. Respiration measurements revealed energetic demands of 1.1±0.4% of body carbon per day for G. wilkitzkii and 1.9±0.6% d^–1 for T. libellula. Feeding experiments with calanoid copepods revealed similar daily rations of 1.9±1.5% d^–1 for T. libellula. In contrast, ingestion by G. wilkitzkii was substantially higher (8.0±5.5% d^–1). These differences in the two amphipods may reflect adaptations to deviating life-styles in the same habitat. T. libellula is an actively swimming pelagic predator, whereas G. wilkitzkii usually stays attached to the ice saving energy by a reduced metabolism. However, it is able to react quickly when prey becomes available. This may be an advantageous strategy in the extreme environment of the Arctic pack-ice where utilising scarce and patchily distributed food sources is essential.

Austin, C.M. and Ryan, S.G.

School of Ecology and Environment, Deakin University, Warrnambool, Australia

Allozyme evidence for a new species of freshwater crayfish of the genus Cherax Erichson (Decapoda : Parastacidae) from the south west of Western Australia and the rapid extinction of the marron (Cherax tenuimanus)

The marron, Cherax tenuimanus (Smith), is one of the most easily recognisable members of the freshwater crayfish genus Cherax. Genetic studies indicate the species contains two genetically distinct forms. One of these forms is widespread and exploited via aquaculture and the other is restricted to single river system, the Margaret River. This paper present allozyme data collected from marron sampled from the Margaret River over a 19 year period which documents the introduction of the widespread form into this river and the subsequent reproductive interactions between the two forms of marron. These data indicate minimal interbreeding between the two form of marron and so justify their recognition as distinct species. An additional outcome of this study is that the Margaret River marron (C. tenuimanus) has been rapidly displaced by the introduced marron (C. sp. nov.). Consequently, urgent conservation measures are required to protect C. tenuimanus and prevent its possible extinction.

Bagnall, R.A. and Frohlich, D.R.

Department of Biology, University of St. Thomas, Houston, TX, USA

Nucleotide sequence and inferred secondary structure of internal transcribed spacer I (rDNA) of Americamysis bahia (Molenock, 1969)

We report the sequence of internal transcribed spacer 1 (rDNA) for Americamysis bahia and propose the first secondary structure for a Crustacean ITS1. Small variations in proposed secondary structures are compared between a Florida population and a Texas Gulf coast population.

Bamber, R.N.¹ and Seaby, Richard M.H.²

¹The Natural History Museum, Cromwell Road, London SW7 5BD, UK ²Pisces Conservation Ltd, IRC House, The Square, Pennington, Hampshire SO41 8GN, UK

The effects of power station entrainment passage on marine planktonic crustaceans

Experiments have been undertaken exposing larval common shrimp (Crangon crangon) and lobster (Homarus gammarus) and adult copepods (Acartia tonsa), to the key stresses of entrainment within power-station cooling-water systems. The apparatus has allowed the testing of mechanical, thermal, chlorine and pressure effects both alone and in combination, the range of the stressors spanning the standard conditions found within a coastal direct-cooled power station. Mechanical stresses affected only lobster larvae; pressure changes affected only the Acartia adults. Residual chlorine caused significant mortality of Acartia and shrimp larvae, but had no effect on lobster larvae even at 1 ppm. The temperature increment significantly affected all three species, with a synergistic influence on chlorine sensitivity in the shrimp larvae, but only unrealistically high temperatures affected the copepods. It is notable that, at least within the species tested, generalizations from the responses of one to those of another are not valid.

Bauer, R.T.

Department of Biology, University of Louisiana at Lafayette, USA

Extended male phase in a protandric simultaneous hermaphrodite, the caridean shrimp Lysmata wurdemanni.

All individuals first develop as a male-phase (MP). With increasing size MP's change to a female-phase (FP) that produces embryos but retains male reproductive function (simultaneous hermaphrodite). However, there are many MP's much larger than the minimum possible size of change to FP. One hypothesis tested was that MP's might benefit from a delayed change to FP if larger MP's are more successful at mating as males than FP's or smaller MP's. Success in insemination of pre-spawning FP's was compared between (1) FP's and small MP's (2) FP's and large MP's and (3) small and large MP's. No significant differences in mating success among sexual or size morphs were found. An alternative explanation is that FP's are capable of changing back to large MP's. However, no sex reversion occurred in groups of FP's reared under either optimal summer conditions (population structure hypothesis) or suboptimal winter conditions (non-breeding season hypothesis).

Bennet-Chambers, M.G.¹ and Knott, B.²

¹School of Biomedical Sciences, Curtin University of Technology, Bentley, WA 6845, Australia ²Department of Zoology, The University of Western Australia, Nedlands, WA 6008, Australia

Sublethal exposure and accumulation of cadmium in Cherax tenuimanus (Smith, 1912) (Decapoda: Parastacidae)

This study investigated the ability of the freshwater crayfish, Cherax tenuimanus (Smith, 1912) to accumulate cadmium in three tissues: hepatopancreas, gills and abdominal muscle. C. tenuimanus (marron) were exposed to 15ppb of cadmium over a 90 day period This was an exposure concentration the animal may encounter within the environment, particularly during periods of high agricultural runoff. Samples of three tissues (10 experimental; 5 controls) were taken at 30, 60 and 90 days, digested, and analysed for cadmium using AAS. There was a significant increase in the cadmium, stored within the hepatopancreas (p<0.0001) and absorbed by the gills (p<0.0001), of the exposed marron cadmium when compared to the controls. Accumulation of cadmium within these tissues also increased over time. However, the abdominal muscle of the exposed marron remained constant, after an initial increase at 30 days. This was possibly an effect of accumulation by the haemolymph surrounding the muscle, rather than regulation of cadmium uptake by the muscle.

Berge, J.

Dept. of Zoology, Tromsø Museum, University of Tromsø, 9037 Tromsø, Norway

Phylogenetical relationships of the amphipod family Stegocephalidae

The amphipod (Crustacea) family Stegocephalidae Dana, 1852 currently consists of 103 known species, most of which are restricted to the bathyal or abyssal zones. The family as a group has a cosmopolitan distribution, although there appears to be a bias towards the South Pacific and the North Atlantic basins (more than 50% of all known species are recorded in these two areas). Most stegocephalid species appear to be micropredators, but a few have also been collected in baited traps. Based upon a phylogenetical analysis of the family, which included approximately 91% of the total number of species, the family is divided into five subfamilies; Andaniexinae, Andaniopsinae, Bathystegocephalinae, Parandaniinae and Stegocephalinae. Morphological characteristics for these subfamilies are presented. At the generic level, the family is divided into 26 genera. At present, the Stegocephalidae is considered to be the sister taxon to the lysianassid group of families.

Berggren, Matz S.

Marine Ecology, University of Göteborg, Kristineberg Marine Research Station, SE 45034, Sweden

Shrimp associations and is it possible to use the problematic word ‘commensalism’?

Habitat choice among animals, marine as well as limnic and terrestrial, is mostly a combination of predator avoidance, food availability, living space, habitat accessibility and competition success. Both the benthic or semi-benthic shallow-water shrimps are rather omnivorous, making predator avoidance one of the major structuring forces the habitat preferences for the shrimps. This forces the shrimp to adapt to and utilize a special habitat, which will result in that the survival will be greater in the selected habitat than in any other habitat. This way of living cryptically on or in a host animal enhances different modifications of the shrimp towards the habitat in the evolutionary processes. Up till now it has normally been labelled ‘commensalism’, using a common defined word for a special type of symbiosis. From what we know today most of these associations are either totally unknown of their true association type or as some turn out to be a sort of ‘micro parasitism’. Therefore to start up a discussion in this subject, an alternative, more generalized term is proposed - 'colalism' - to label these unknown associations.

Berkenbusch, K.

National Institute of Water and Atmospheric Research, PO Box 11-115, Hamilton, New Zealand

Ecosystem engineering by a burrowing ghost shrimp: not a 'just so' story

The ecological concept of ecosystem engineering has recently been proposed to describe aspects of the relationship between organisms and their environment which are not direcly trophic or competitive. Since the initial reporting of the idea little work has been undertaken to formally assess potential ecosystem engineers in the marine environment, or to address questions which relate to the concept. Biological and ecological data for the burrowing ghost shrimp Callianassa filholi (Decapoda: Thalassinidea) allowed for a formal assessment of this species as an ecological engineer and showed that despite a low population density and the short durability of its burrow structures, Callianassa filholi affects a number of resource flows by its large lifetime per capita activity. Furthermore, the study of Callianassa filholi revealed the probability of interactions between antagonistic ecosystem engineers and the difficulty associated with separating the related concepts of keystone species and ecosystem engineering.

Bluhm, B.A., Brey, T., Klages, M. and Arntz, W.E.

Alfred-Wegener-Institute for Marine and Polar Research, Bremerhaven, Germany

Age determination in Antarctic Crustacea using the autofluorescent pigment lipofuscin

Determination of basic population parameters in long-lived Crustacea is hindered by the lack of appropriate methods for age determination. This study used the pigment lipofuscin as an age marker in the Antarctic decapod Notocrangon antarcticus and the amphipod Waldeckia obesa from the Weddell Sea. Resin brain sections were digitally recorded by confocal microscopy and images were subsequently analysed. A modal progression analysis of the lipofuscin concentration-frequency distribution revealed 8 and 5 regularly-spaced modes (assumed to reflect age classes) for N. antarcticus and W. obesa, respectively. No regular modes were obvious from the length frequency-distributions. The average yearly pigment accumulation rates were nearly linear. Lipofuscin-based estimates of growth parameters, P/B-ratios and mortality-rates indicate that both species are slow-growing, long-lived, and have low productivity compared to congeners from lower latitudes. Within the Antarctic benthos, however! P/B-ratios of the crustaceans are higher than those of most other taxa.

Bond-Buckup, G. and Castro, T.S.

Instituto Biociências, Departamento de Zoologia, PPG Biologia Animal, UFRGS, Sao Paulo, Brazil

The morphology of cardiac and pyloric foregut of Aegla platensis (Decapoda, Anomura, Aeglidae)

The aeglid crabs occur in streams, cavern rivers and lakes of subtropical and temperate regions in South America. The ossicle complex found in brachyura and anomura cardiac foreguts may reveal evolutionary connections between these two groups. The samples were collected from a Gravataí River tributary creek, in RS, the southernmost region in Brazil. They were separated by sex, dissected and prepared for an optical and electronic scanning microscopy analysis. It was found that the cardiac foregut consists of seven ossicles composing the gastric mills, six ossicles which provide its lateral support, but also of other seven structures such as valves and teeth. The pyloric foregut has nine ossicles, three valves, two ampullaes with many setose ridges that act as a food filter. Differences with other Anomura were found concerning the shape, size, calcification degree and lack or addition of one or more ossicles.

Boschi, Enrique E.

Instituto Nacional de Investigación y Desarrollo Pesquero and CONICET Casilla de Correo 175, 7600 Mar del Plata, Argentina

American anomuran decapods: diversity and distribution

The number of species of Anomuran in the continental shelves of Americas between the Arctic and Cabo de Hornos (Southern South America) at depths of no more than 300 m in the Atlantic and Pacific Oceans was estimate as 510 (Boschi 2000). Analyzing the distribution of species for zoogeographical provinces it is observed that in the tropical ones there exists the biggest biodiversity: caribbean with 205 species, includes the Caribbean Sea and part of Mexico Gulf and the Panamic one, which include the East Pacific with 165 species. The minor diversity is found in the provinces of high latitude: The Arctic with 9 species and the Magellanic with 22 species. This characteristic of the distribution is of clinal type, decreasing to temperate and cold regions, which is observed in the other groups of Decapoda. In the numerical importance the Anomura are the third group after Brachyura and Caridea.

Boudrias, M.A.

Marine and Environmental Studies, University of San Diego, USA

Thrust generation by the drag-based propulsive limbs of Eurythenes gryllus (Crustacea: Amphipoda).

Amphipods use a drag-based mode of paddle propulsion when swimming, with three pairs of abdominal pleopods providing the propulsive thrust. I measured the forces produced by pleopods from the large deep-sea lysianassid, Eurythenes gryllus, in the power and recovery stroke positions. Results suggest that the overall size and shape of the propulsive paddle, not the small-scale characteristics of the setae and setules, dominate force production. The net thrust (power force minus recovery drag) is statistically identical to the force yield of the power stroke suggesting a highly efficient recovery stroke with negligible effects on net thrust production. Paired pleopods generate less than twice the net thrust of two single pleopods. Direct measurements of force by paired pleopods on the power stroke yield drag coefficients that are significantly lower than flat plate values. This implies that total thrust must take the leakiness of pleopods into account for any calculations of thrust.

Boudrias, M.A.¹ and German, D.²

¹Marine & Environmental Studies, University of San Diego, USA. ²Department of Biology, California State University, Fullerton, USA

Burrowing behavior of the vernal pool ostracod Cypris pubera.

We observed several population-wide burrowing events in Cypris pubera during five successive wet-dry cycles of a vernal pool. In late spring, burrowing occurred only in a portion of the pool heated by direct sunlight. We performed laboratory experiments to examine the effect of elevated temperatures on population-wide burrowing. Our results indicate that temperature alone is not the determining factor. It does affect location in the vernal pool since ostracods spend 85% of their time on a surface and only 15% in the water column. Further observations of these burrowing events suggested that multiple seasonal factors (water level, temperature, and crowding) impacted burrowing. On two separate occasions C. pubera underwent torpor during the dry segment of the pool cycle, which was supported by the immediate presence of large sub-adults after rehydration. Thus the burrowing behavior may correlate with torpidity and allow Cypris pubera to dominate the vernal pool community more rapidly.

Boxshall, Geoff

The Natural History Museum, London SW7 5BD, UK

Arthropod evolution and the origin of the Crustacea: a history in three parts

Insights from developmental genetics continue to inform our understanding of relationships between major groups of Arthropods. Analysis of molecular sequence data continues to reinforce the concept of a close affinity between the Crustacea and the Hexapoda. How do our interpretations of morphology fit into the new order of things arthropodan? In this contribution I seek to distinguish between two key tagmatization processes: 1) cephalization by sequential incorporation of body segments into an anterior cephalon, and 2) cephalization by progressive specialization of ancestral multifunctional and tripartite limbs, to perform typically cephalic functions such as food capture and gathering sensory input. The dominant mode of evolutionary change resulting in such specialization is oligomerization (the trend towards reduction of body and limb segments and setation). However, simplistic assumptions that more parts equate to the plesiomorphic state and that fewer parts equate to the apomorphic state are unsupportable. Numerous examples of novel structures arising on limbs and of secondary multiplication of limb parts can be found in the Crustacea including the origin of epipodites and the formation of antennular and antennal flagellae.

Boyce, S.L., Spears, T. and Abele, L.G.

Department of Biological Science, Florida State University, Tallahassee, FL 32306-1100, USA

Molecular phylogeny of the Calappidae (Crustacea: Decapoda: Brachyura)

Crabs of the brachyuran family Calappidae sensu lato are a problematic group with respect to their phylogenetic relationships. Traditionally classified as four subfamilies (Calappinae, Hepatinae, Matutinae, and Orithyiinae) within a single family, Calappidae, recent physiological and larval evidence and morphologically based cladistic analyses have questioned this view. We have undertaken a molecular study to test hypotheses concerning calappid phylogeny. Approximately 650 base pairs of mt16S rDNA were obtained for representatives of eight genera (13 species) from all four subfamilies and for other families previously implicated in calappid phylogeny (e.g., Dorippidae, Leucosiidae, Portunidae, and Xanthidae). Parsimony and likelihood analyses do not support a monophyletic Calappidae. Instead, a monophyletic subfamily Calappinae is found that includes (Mursia + Platymera) and (Calappa + Cryptosoma) clades. Portunids appear as the sister group to the Calappinae with moderate bootstrap support. The Hepatinae (Hepatus + Osachila) are monophyletic, but relationships among the other calappid subfamilies are equivocal pending additional data.

Bradford-Grieve, J.M.

National Institute of Water and Atmospheric Research, Wellington, New Zealand

Colonization of the pelagic realm by calanoid copepods

The evolution of calanoid copepods probably extends back into the mid Paleozoic. Environmental change from the Paleozoic through to the Tertiary is reviewed. Turbidity, water clarity, oxygen, and tectonically induced changes in the morphology of the oceans are probably all important drivers of calanoid evolution and their invasion of the pelagic realm. Current views of the phylogeny of the Calanoida are presented as well as a review of some recent work on metabolic potential, female genital system, and nervous system. It is hypothesized that ancestors of the Arietelloidea and Diaptomoidea invaded the water column in the Devonian at a similar time to the Ostracoda and that the ancestors of the Calanoidea - Clausocalanoidea, with their myelinated axons, arose in the Permian during the major deep ventilation of the ocean. Present day distributions of some Diaptomidae, Centropagidae, and Calanidae suggest that these families successfully came through the Jurassic/Cretaceous expansion of the oxygen minimum zone and the K-T event.

Brandt, Angelika

Zoological Institute and Zoological Museum, Martin Luther-King-Platz 3, 20146 Hamburg, Germany

Antarctic isopod deep-sea biogeography - the importance of the ANDEEP expeditions

The deeper waters of the Scotia and Weddell Seas are some of the least explored parts of the world’s oceans and we know almost nothing about isopods that inhabit them. By contrast, we know that the present-day benthic animals of the Antarctic continental shelf exhibit many striking and unusual features, including gigantism, longevity, an extraordinarily high degree of endemism, and absence of taxa which are abundant in similar environments elsewhere. Such attributes are believed to reflect the geographical and hydrographical isolation of the shelves and their special environmental characteristics. Periodic extensions of the ice sheet and deep-water production may have enhanced speciation from the continental shelf down into the deep sea of the world’s oceans. For a better understanding of Antarctic deep-sea biodiversity and biogeography ANDEEP [ANtarctic benthic DEEP-sea biodiversity (ANDEEP): colonization history and recent community patterns], an international project to investigate the deep-water biology of the Scotia and Weddell seas from F/S Polarstern are planned.

Brockerhoff, Annette M.

Department of Zoology, University of Canterbury, Private Bag 4800, Christchurch, New Zealand

Influence of sex ratio on oviposition phenology of two intertidal grapsid crabs

The mating strategies of two grapsid crabs were studied in the field and laboratory to determine factors that influence female receptivity. In both species each female is receptive for only a few days shortly before oviposition. In field cage experiments, isolated Hemigrapsus edwardsi females stayed receptive significantly longer (mean 5.0 d) than females kept together with males (3.2 d), suggesting that H. edwardsi females are able to control receptivity. Laboratory experiments with Hemigrapsus crenulatus gave similar results suggesting that female receptivity control also occurs in this species. When previously isolated receptive females were joined with a male, they usually laid eggs within 24 h after mating. Females that were continuously exposed to males in different sex ratios did not show significant differences in their duration of receptivity but in the total number of matings. Interestingly, in the laboratory females became receptive several weeks before those in the field, and they had a shorter duration of receptivity. These observations are critical for studies on sperm competition which is thought to be an important component of sexual selection.

Brösing, A., Richter, S. and Scholtz, G.

Comparative Zoology, Institute for Biology, Humboldt-University of Berlin, Berlin, Germany

The brachyuran foregut-ossicle system and its purpose for phylogenetic studies

The foregut ossicle system of 42 species of Brachyura was examined and the ossicle-terminology of the brachyuran foregut was revised, which includes 37 ossicles. All described ossicles were documented by drawings and photographs. For a first cladistic analysis, some 30 characters of the foregut-ossicles were analysed using the computer program NONA. 1. The suggested monophyly of the Podotremata is not confirmed. The Dromiacea (Guinot, 1977) (including Homolodromiidae, Dynomenidae and Dromiidae) is the sistergroup to the other brachyuran crabs. So it seems that the Podotremata is paraphyletic. 2. The Homolidae is the sistergroup to the Raninidae + Eubrachyura. This shows that also the Archeobrachyura (Guinot, 1977) (including Poupiniidae, Latreillidae, Homolidae, Cyclodorippidae, Cymonomidae and Raninidae) is not monophyletic. 3. The sistergroup-relationship between Palicidae (a family of the Heterotremata) and Thoracotremata indicates a paraphyletic Heterotremata. This sistergroup relationship has also been suggested by Schubart et al. (1998) based on molecular data from the 16S rRNA gene. The congruent results with different character sets provide a strong evidence for this relationship. 4. The Thoracotremata is monophyletic supported by a number of apomorphic characters.

Buckup, Ludwig and Grala, Márcia M.

Dep. de Zoologia, Inst. Biociências, Univ. Federal do Rio Grande do Sul, Porto Alegre, Brazil

The burrows of Parastacus defossus Faxon, 1898 (Crustacea, Parastacidae)

Parastacus defossus is a burrowing crayfish, living in clayey soils in South Brazil and Uruguay. A population from Mariana Pimentel Municipality, RS, Brazil (30 20´S 51 22´W) was studied. An area of 100 m² was delimited and divided into 100 quadrats. All entrances in each quadrat were graphed. The dispersion pattern of the openings was investigated. The expected frequencies of the Poisson distribution do not fit the observed frequencies, consequently the openings are not randomly dispersed. The negative binomial was a good fit to the data, permitting to conclude that the population is not randomly dispersed, showing an aggregated dispersion pattern. The possible motives for the aggregation are discussed. Changing of place and number of openings was observed and accompanied in 20 quadrats chosen lot by lot, from August 1998 to July 1999. The burrows are sealed during summer drought and new apertures are prepared during winter. Gypsum casts from the burrows were obtained and studied.

Bueno, A.A.P. and Bond-Buckup, G.

Instituto de Biociências, Departamento de Zoologia e PPG Biologia Animal, UFRGS, Sao Paulo, Brazil

Feeding habits of Aegla ligulata Bond-Buckup & Buckup (Decapoda, Anomura, Aeglidae)

The analysis of stomach contents of Aegla ligulata specimens from a tributary creek of the Tainhas River, RS, Brazil, allowed the study of its feeding habits. A total of 369 males and 336 females were caught from August 1999 to August 2000. Dietary analysis was based on four methods: 1)Visual estimate of stomach fullness immediately after its removal; 2)Frequency of occurrence; 3)Percentage point methods; 4)Index of relative importance (IRI), combining frequency of occurrence (FO), percentage of total biomass and percentage of total numbers consumed. The bulk of the stomach contents comprised plant remains, algae, sand, dipteran larvae, nymphs of Ephemeroptera and Plecoptera, Trichoptera, Coleoptera. Stomach fullness was not sex related. Significant differences were revealed in relative proportions of prey items between males and females. The investigation showed that Aegla ligulata is omnivorous, feeding on benthic animals and plants.

Bueno, S.L.S.¹, Rocha, S.S.¹, Arantes, I.C.^{1, 2}, Kiyohara, F.¹, Silva, H.L.M.¹, Mossolin, E.C.¹, Melo, G.A.S.³, Magalhães, C.⁴ and Bond-Buckup, G.⁵

¹Department of Zoology, Institute of Biosciences, University of São Paulo, São Paulo, SP, Brazil ²University Brás Cubas, São Paulo, SP, Brazil ³Museum of Zoology, University of São Paulo, São Paulo, SP, Brazil ⁴National Research Institute of the Amazonia (INPA), Manaus, AM, Brazil ⁵Department of Zoology, Institute of Biosciences, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil

Freshwater decapod diversity in the State of São Paulo, Brazil

The BIOTA-FAPESP Programme is a major State scientific effort that aims the study of the biodiversity in the State of São Paulo, Brazil. As part of this programme, the present study focuses on freshwater decapods. This 4-year field survey started in mid-1999. Samples have been collected from several representative areas, mainly from environmentally protected sites and ecological sanctuaries. Decapods were collected with the aid of seines, traps or were manually removed from their shelters. So far, results from field collections, augmented by additional data of deposited specimens from museums, include trichodactylid crabs, aeglid anomurans, caridean shrimps and cambarid crayfish, totaling 31 species within 9 genera. Data are being used for evaluating endemism, for extending the knowledge on geographic distribution, for the recognition of established populations of exotic species and to associate vanished decapod populations from some areas as a result of environmental destruction carried out by man.

Calazans, D.

Departamento de Oceanografia - FURG Cx. Postal 474, Rio Grande, CEP 96.201-900, Brazil

Seasonal larval composition and abundance of shrimps in the surrounding area of the Patos Lagoon mouth

Larval phases of seven species of shrimps were found in the surrounding area of the Patos Lagoon mouth. Zooplankton and hydrographic samples in four seasonal cruises were undertaken between November 1982 and August 1983 in the coastal marine area around the Patos lagoon mouth. Seasonal species composition and their abundance were compared showing variations according to the season. Artemesia longinaris and Pleoticus muelleri were well represented throughout the year; Acetes americanus was present only during summer; Sicyonia typica only during autumn; Lucifer faxoni during summer and autumn; Peisos petrunkevitchi during autumn and winter and Farfantepenaeus paulensis during spring and summer.

Calazans, D. and Fernandes, F.P.A.

Departamento de Oceanografia, FURG Cx. Postal 474, Rio Grande, CEP 96.201-900, Brazil

Seasonal occurrence and abundance of brachyuran megalopa in the estuarine region of Patos Lagoon, Brazil (32 5'S 52 5'W)

Recruitment of brachyuran megalops was studied in the estuarine region of the Patos Lagoon where zooplankton samples with a conical 330(m mesh net were taken biweekly, in three positions near to the mouth of the lagoon and the coastal marine surrounding area. A total of 1.636 megalops were collected. During the summer Callinectec sapidus megalops were the most abundant with 46% of megalops caught( during autumn the most abundant was Chasmagnathus granulata with 26% of megalops collected and during spring Pinnixa sp. was the most abundant with 46% of megalops. During winter none megalops was collected. In the autumn were present 6 species Cystograpsus angulatus, C. affinis, C. altimanus, Pinnixa sp., Chasmagnathus granulata and Hepatus pudibundus. Abundance to all species shows to be sporadical like Callinectes sapidus were more than 90% of megalops were catch in one day only.

Castro, P.

Biological Sciences Department, California State Polytechnic University, Pomona, California, USA

Symbiosis, To Be or Not To Be

The participants of the symposium on the biology of decapod crustacean symbioses will review some recent developments on the biology of some of the symbiotic associations among decapods. Instances of symbiosis, close associations between two different species, are common among decapods. In fact, several families and subfamilies consist exclusively of symbiotic species. Several terms have been used to describe the many variations of symbiotic associations: commensalism, mutualism, parasitism, and others. The presence or absence of "harm" or "benefit" among the associates have traditionally been used to define these categories. Not only these terms can be ambiguous and subjective but also little is known about the biology of most of these associations. What is symbiosis? What terms should be used to define the categories of symbiosis? Should these terms be used at all?

Chan, Siu-Ming

Dept. of Zoology, The Univeristy of Hong Kong, Pokfulam Road, Hong Kong

Evidence for multiple vitellogenin genes expressions by the hepatopancreas and ovary of the shrimp Metapenaeus ensis.

In Metapenaeus ensis, the peak of vitellogenesis occurs during the premolt stage. We identified a 170 kDa polypeptide as the major egg yolk protein in the ovary. The anti-170 kDa antibody detected the presence of vitellogenin (Vg) in the ovary and only weak signal was recorded in the hepatopancreas. By genomic PCR and Southern blot analysis, about 3-4 Vg genes were identified in the shrimp genome. These Vg genes are highly conserved and each carries two small introns within the 1.0 kb partial Vg gene. Within the same 5' region of the Vg gene, similar gene organization also occurs in the fresh water shrimp Macrobrachium rosenbergii and the gene organization is comparable to other invertebrate and vertebrates Vg genes. Northern blot analysis detected Vg transcripts abundantly in the hepatopancreas and slightly in ovary of mature females. RT-PCR of hepatopancreas and ovary RNA resulted in the subcloning of two highly homologous cDNAs. Because of the apparent high degree of similarity in amino acid sequence and gene organization for Vg of M. ensis and M. rosenbergii, the expression of Vg in M. rosenbergii was re-examined. Contrary to the previous report in M. rosenbergii, we provided evidence that both the ovary and the hepatopancreas express Vg in this species. The difference in relative level of Vg expression in the ovary of the marine and fresh water shrimp suggests the importance of Vg to the supply of nutrient for larval development. In summary, the shrimp Vg gene is encoded by multiple copy of genes and it is expressed in the hepatopancreas and ovary of the adult females in both the M. ensis and M. rosenbergii.

Chapelle, G.¹, Coleman, C.O.² and Gonzalez, E.³

¹Institut Royal des Sciences Naturelles de Belgique, Rue Vautier 29, B-1040 Bruxelles, Belgium ²Museum für Naturkunde, Humboldt-Universität, D-10099 Berlin, Germany ³Ira C. Darling Center, University of Maine, Walpole, Maine 04573, U.S.A

Revisiting the species flock of Amphipoda in Lake Titicaca

Until recently, the described amphipod fauna of the lake consisted of 11 species, all from the genus Hyalella. However, using the exceptional material sampled in 1937 by a British expedition, Crawford & Lincoln tentatively ascribed most of the 70000 specimens to 104 morphotypes. This study undertaken in the seventies was advertised in a 1993 workshop, giving us access to this outstanding collection only in 2000. A first look at the collection confirmed that the main habitus represented by the described species were connected by morphological gradients. Whether these morphotypes reflect isolated populations, hence separated species, remains to be checked through both morpholy and genetics. Another interest of this collection resides in that it was sampled prior to the introduction of fish known to prey heavily on amphipods, thus providing a providential base line to estimate their impact on this endemic fauna.

Chiba, S. and Goshima, S.

Department of Marine Biological Science, Hokkaido University, Hokkaido, Japan

The advantage of male protandrous pandalid shrimp in delaying sex-change

In protandrous species, the change from male to female generally considers that large male which delay the timing at sex-change is not adaptive to enhance reproductive success. This study examined the male reproductive success with body size and estimated the adaptive significance of large males of protandrous shrimp, Pandalus latirostris. Field observation showed that several males of P. latirostris compete for a female to fertilize egg during breeding season. Effects of male body size on the fertilization success and the male-male competition for mate were examined by laboratory experiment. Small males could adequately inseminate females as well as large male in absence of competitor condition. However, large males increased the probability of fertilization in the male-male competition. Therefore, the male reproductive success increases with body size and delaying sex-change is adaptive in this shrimp.

Chu, K.H.¹, Ho, H.Y.¹ and Chan,T.Y.²

¹Department of Biology, The Chinese University of Hong Kong, Hong Kong ²Institute of Marine Biology, National Taiwan Ocean University, Keelung, Taiwan

Molecular phylogeny of the mitten crabs, Eriocheir s. l. (Brachyura: Grapsidae)

Eriocheir was previously considered to comprise of four species (E. japonica, E. sinensis, E. recta, and E. leptognathus), but recent taxonomic revision has recognized five species and split them to three genera. The genus Eriocheir is restricted to three species (E. sinensis, E. japonica, and E. hepuensis) and two distinct genera are established for the other two species (Neoeriocheir leptognathus and Platyeriocheir formosa). Yet the proposal is still controversial among crustacean taxonomists. This study aims to elucidate the phylogeny of the species of Eriocheir s. l. based on DNA sequence analysis of mitochondrial 16S rRNA, cytochrome c oxidase I (COI), and the first internal transcribed spacer (ITS-1) of nuclear rRNA. The results show that the three Eriocheir s. s. species are closely related to each other. The 16S rDNA sequences of the sister taxa E. sinensis and E. hepuensis are identical and their COI nucleotide divergence is about 5%, indicating that they are products of recent radiation. N. leptognathus is the most distantly related taxon within the group, with 12-15% COI divergence to the other species. In general, our results support the distinction of the crab based on morphological features as in the recent revised taxonomy, although the small genetic divergence among the crabs suggests that the five species can be grouped into a single genus.

Clark, Paul F.¹ and Calazans, Danilo²

¹Department of Zoology, The Natural History Museum, London, England ²Departamento of Oceanografia, Fundaçáo Universidade of Rio Grande, Rio Grande, Brazil

A review of the decapod and euphausiid larval terms, stage and phase

The use of the decapod and euphausid larval terms phase and stage are reviewed and clarified. Only four phases are recognised and recommended: nauplius, zoea, megalop and adult. These are defined and are submitted for consideration as standard within the Decapoda and Euphausiacea. A number of larval terms in general use are regarded as redundant.

Clark, Paul F.¹, Ng, Peter², Cuesta, Jose A.³ and Schubart, Christoph⁴

¹Department of Zoology, The Natural History Museum, London, England ²Department of Biological Sciences, National University of Singapore, Singapore 119260 ³Department of Biology, University of Louisiana at Lafayette, Lafayette, USA ⁴Biologie 1, Universität Regensburg, Germany

An appraisal of the systematics of the family Ocypodidae sensu lato using zoeal, adult, and DNA evidence

The morphology of 39 first zoeal stages currently assigned to the Ocypodidae and Camptandriidae was analysed for a phylogenetic study. Macrophthalmus zoea I present a consistent suite of characters but the inclusion of three species within the genus may require revision. The assignment of Shenius to the Macrophthalminae has already been questioned. Larval, adult and DNA characters all now confirm the affinity of Shenius with Ilyoplax and Scopimera species. On zoeal, adult and DNA evidence the Heloeciinae appears to be a monotypic taxon separate from Ucides (now Ocypodinae) and other Ocypodidae sensu lato. However, although the larval evidence confirms Camptandriidae monophyly, Dotilla systematics remains uncertain. This genus may be intermediate between the Dotillinae, Ilyoplax and Scopimera, and the camptandriids, representing a distinct taxon. Finally, analysis of larval, adult and DNA data suggest that the subfamilies comprising the ocypodids all require revision to familial status as currently recognised for the Camptandriidae.

Cobo, V.J.

Department of Biology, University of Taubaté - UNITAU, São Paulo, Brazil and NEBECC - Group of Studies on Crustacean Biology, Ecology and Culture

Breeding period of the spider crab Mithraculus forceps (Majidae, Mithracinae) on Southern Brazilian Coast

The goal of this research was report the breeding period of the spider crab M, forceps, based on the monthly frequency distribution of ovigerous females. Monthly collections were carried out from January to December 2000. Ovigerous females were recorded in hole sampled months, representing no less than 50% of the adult females, with the main peak in September which represented 100% of the adult females. For the M. forceps was observed a continuous reproduction pattern, as frequently reported for another crabs of tropical and subtropical regions.

Cobo, V.J.

Department of Biology, University of Taubaté - UNITAU, São Paulo, Brazil and NEBECC - Group of Studies on Crustacean Biology, Ecology and Culture, Brazil

Breeding period of the arrow crab Stenorhynchus seticornis (Majidae, Inachinae) from Couves Island, Southern Brazilian Coast

The aim of this study was report the breeding period of the arrow crab S. seticornis, based on the monthly frequency distribution of ovigerous females. Monthly collections were accomplished from January to December 2000. Ovigerous females were recorded in all sampled months, representing no less than 50% of the adult females, with peaks in March and April, representing 90.3% and 96.9% of the adult females, respectively. For the arrow crab was observed a continuous reproduction pattern, as commonly founded to decapods of tropical and subtropical regions.

Cockcroft, A.C.

Marine and Coastal Management, Private Bag X2, Rogge Bay, Cape Town South Africa

The management of South African crustacean fisheries: past, present and future

Three commercial fisheries for crustaceans occur off South Africa. Two of these are trap-fisheries targeting individual rock lobster species, namely: Jasus lalandii, in shallow water (< 100 m) along the west coast and Palinurus gilchristi, in deep water (100 - 200 m) along the south coast. A multi-species crustacean trawl fishery operates off the east coast. Prior to the Marine Living Resources Act of 1998, which formally recognised existing subsistence and informal fisheries for the first time, management of crustacean resources focussed almost entirely on the commercial sector. The Act therefore provided the dual challenge of incorporating previously disadvantaged portions of the community into the structures of well-established fisheries and the formal management of subsistence components of these fisheries. This paper reviews the status of the important crustacean resources and highlights past, present and future management options for these important South African fisheries.

Coelho, Vânia R.

Senior Research Scientist, Columbia University, Biosphere 2 Center, P.O. Box 68, Oracle, AZ 85623, USA

Intraspecific behavior of two pair-bonding thalassinidean shrimp, Axianassa australis and Pomatogebia operculata.

The intraspecific behavior of two pair-bonding thalassinidean species, Axianassa australis and Pomatogebia operculata was investigated. A. australis inhabits burrows built in mud flats while P. operculata lives inside corals. Specimens of A. australis were collected with a yabby pump at Praia do Araçá, São Sebastião, SP, Brazil. P. operculata individuals were extracted from Mussismilia hartti corals collected in several dives at Nova Viçosa Reef, Abrolhos, BA, Brazil. Behavioral observations were conducted in aquaria. The recognition display of both species initiates with individuals repeatedly sliding its antennae over the antennae of the other. However, in P. operculata, this display continues with the specimens touching the telson of each other with their antennae. In A. australis no fights were observed between males and females even if the specimens were collected from different burrows, although strong agonistic behavior was recorded between individuals of the same sex. Fights were not recorded between P. operculata male-female pairs found in the same burrow, but an aggressive behavior was observed between specimens of opposite sex found in different burrows, as well as between two males. In both species fights eventually ended with the death of one of the individuals.

Coleman, C.O.¹, Chapelle, G.² and Gonzalez, E.³

¹Museum für Naturkunde, Humboldt-Universität, D-10099 Berlin, Germany ²Institut Royal des Sciences Naturelles de Belgique, Rue Vautier 29, B-1040 Bruxelles, Belgium ³Ira C. Darling Center, University of Maine, Walpole, Maine 04573, U.S.A.

Variability of hyallelid Amphipoda in Lake Titicaca

Like the well described adaptive radiation of amphipods in Lake Baikal, the Hyalellidae from Lake Titicaca exhibit another example of an amazing morphological diversity of intralacustric evolution. On the basis of the huge amphipod collection of Titicaca amphipods, stored at the Natural History Museum London, populations of selected species are compared. These populations are morphologically and morphometrically characterized. Specimens from a certain population are morphologically very similar to each other, but differ strongly from representatives of other populations collected from other parts of the lake. A comparable case of distinct populations is shown from an amphipod species from Lake Baikal. In some cases the differences were so striking that these populations will be described as new species.

Colpo, K.D. and Negreiros-Fransozo, M.L.

NEBECC (Group of Studies on Crustacean Biology, Ecology and Culture) Departamento de Zoologia, IBB, UNESP, Botucatu (SP), Brazil

Comparative analysis of the reproductive potential of U. vocator (Herbst, 1804) in three subtropical mangroves

The brachyuran crabs of the genus Uca, commonly known as fiddler crabs, are very abundant in the South American mangroves, living in burrows built in the sediment and feeding on its organic matter. The reproductive biology of U. vocator was investigated in three Brazilian mangroves: Itapanhaú (23 49'14"S, 46 09'14"W), Indaiá (23 24'51"S, 45 03'14"W) and Itamambuca (23 24'43"S, 45 00'73"W). The aspects analyzed were fecundity, sexual maturity and size of ovigerous females. The crabs were captured during low tide by two collectors for 15 minutes. Organic matter content of the sediment from each locality was determined. The morphometric measures of each crab were: carapace width (CW), cheliped propodus length (CPL) and abdomen width (AW). Organic matter amount and size of ovigerous crabs increase from Itapanhaú to Itamambuca, being intermediate in Indaiá. Uca vocator presented variation in the size of onset sexual maturity and fecundity index in function of food availability in each mangrove, evidencing the reproductive potential is closely related to nutritional resources of the habitat.

Coman, F.E.^{1, 2}, Connolly, R. M.² and Preston, N.P.¹

¹CSIRO Division of Marine Research, PO Box 120, Cleveland, 4163, Australia. ²School of Environmental and Applied Sciences, Gold Coast campus, GriffithUniversity, PMB 50, Gold Coast Mail Centre, Queensland, 9726, Australia

Zooplankton and epibenthic fauna in shrimp ponds: factors influencing assemblage dynamics

We examined the crustacean zooplankton and epibenthos in a commercial shrimp pond in subtropical Australia. Zooplankton numbers and biomass ranged from 111.7 ind. l^–1 (324 (g l^–1) to 8.3 ind. l^–1 (44.2 (g l^–1). A rapid decline in abundance, immediately after the pond was stocked with shrimp postlarvae, indicated that copepods were a significant source of food for the postlarvae. Subsequent peaks in zooplankton abundance were lower than during pre-stocking and principally due to barnacle nauplii. Sergestids (Acetes sibogae) and amphipods were the most abundant epibenthos. Total abundance peaked at 14 ind. m^–2 and the biomass at 0.8 g m^–2, too low a level contribute a significant source of nutrients for juvenile shrimp. Variation in physico-chemical characteristics of the pond did not appear to impact significantly in the abundance and composition of the zooplankton or epibenthos. Instead, recruitment and predation appear to be the dominant factors influencing the dynamics of these assemblages.

Conides, A.J.¹, Apostolopoulou, M.², Thessalou-Legaki, M.², Nikolaidou, A.² and Lumare, F.³

¹National Centre for Marine Research, Ag. Kosmas, Hellinikon, Athens 166 04, Greece ²Department of Biology, Laboratory of Zoology and Museum, University of Athens, Ilisia 157 71, Athens, Greece ³ Shrimpculture Research Unit, University of Lecce, via Monterroni, 73100 Lecce, Italy

Maturity and reproduction of the mudprawn Upogebia pusilla population in western Greece

The mudprawn, Upogebia pusilla, population in Western Greece is heavily exploited today by fishing for use as bait. The method of fishing (with water pumps) is disastrous for the population causing stress. Monthly samples are taken from the area since 1999 for an ongoing research project. The first egg-carrying females appear around mid January (January 12 for 1999, January 18 for 2000 and February 4 for 2001). The reproduction period lasts between January and September following a double peak mode. The last egg-carrying female is observed during mid-September (September 12 for 1999 and September 23 for 2000). Almost all females of Upogebia show an intermediate gonad maturity stage between mature gonad and spent gonad. These females have a half-empty ovary and carry eggs on their abdomen, indicating that they are capable to reproduce again later during the same period. Gonad-somatic Index fluctuation indicates two peaks in reproduction: during February and June.

Conides, A.J.¹, Lumare, F.², Papaconstantinou, C.¹, Scordella, G.² and Kapiris, K.¹

¹National Centre for Marine Research, Ag. Kosmas, Hellinikon, Athens 166 04, Greece ²Shrimpculture Research Unit, University of Lecce, via Monterroni, 73100 Lecce, Italy

Skewed sex ratios and reproduction in an intensively exploited shrimp Penaeus kerathurus population in western Greece

The shrimp Penaeus kerathurus is a native in the Mediterranean region and it is considered as a valuable commercial product. In Greece, the shrimp can be found in Amvrakikos Gulf (Western Greece) and it is heavily exploited as a single-species fishery. Monthly samples were taken between 1999 and 2000 (EU research project DG XIV-Fisheries/037/98). Monthly sex ratios (as males/females) were found fluctuating between 0.5 and 2.65. This indicated that males dominate the samples during most of the year. In addition, the males arrive first in the mating grounds. The females arrive approximately 20 days later. Reproduction occurs between April and September. The maturation stimulus is the rapid increase of temperature by 7.70 C during March. This is followed by the initiation of migration towards the coastal zone for mating and then by spawning. The reproduction occurs in a single peak mode during July as shown from GSI index (10-12%).

Conroy-Dalton, S. and Huys, R.

Department of Zoology, The Natural History Museum, Cromwell Road, London SW7 5BD, UK

Character transformation and polyphyly in the Ancorabolidae (Copepoda: Harpacticoida)

Representatives of the Ancorabolidae are among the most visually striking harpacticoid copepods, instantly recognisable by their ornate body morphology. Despite its long history, the validity of the family as a whole and the monophyletic status of the two sub-families (Ancorabolinae and Laophontodinae) have until now, never been properly addressed. Recent studies revealed novel, phylogenetically significant characters derived from the remarkable patterns displayed by sensory sensillae and the integumental processes with which they are associated. Assessment of the homology of these sensillar patterns provides a key to the relationships and phylogeny within the Ancorabolinae. Distinct lineages are revealed, and unequivocal evidence is provided for their independent evolution from unadorned ancestors. Phylogenetic analysis of the Ancorabolidae shows the taxon to be highly polyphyletic, comprising at least four distinct lineages. Mounting evidence indicates the roots of these lineages to lie within the heterogeneous family Cletodidae, where they represent specialised or terminal branches.

Cook, B.¹, Choy, S.² and Davie, J.³

¹Griffith University, Nathan, Queensland, Australia. ²Queensland Department of Natural Resources and Mines, Brisbane, Australia. ³University of Queensland, Gatton, Queensland, Australia

Potential ecological Impacts of translocating Redclaw Crayfish, Cherax quadricarinatus.

The direct and indirect ecological impacts of the redclaw crayfish, Cherax quadricarinatus, on other aquatic macroinvertebrates outside its natural range of distribution were examined. Direct ecological impacts to macroinvertebrate fauna were determined by examining the interspecific and intergeneric agonistic behaviour of redclaw, its competition for shelters, and community establishment potential. Indirect impacts to macroinvertebrates were assessed via substrate and macrophyte perturbations. Redclaw is dominant over the local crayfish (yabby), Cherax depressus, and the local prawn, Macrobrachium australiense. Subadult yabbies dominate subadult redclaw, however mature redclaw dominate over mature yabbies. Both subadult and mature redclaw dominate over the prawn. It is unlikely that substrate perturbations by translocated redclaw would result in impacts to local macroinvertebrates. However, redclaw may have the potential to impact on macrophytes and associated macroinvertebrate fauna if they establish at high densities. It has been postulated that redclaw cannot become established where long-finned eels, Anguilla reinhardtii, occur. It was observed that the presence of this predator reduces activity in subadult redclaw, but did not seem to have the same effect on mature adults. It is concluded that eels are unlikely to control the spread and establishment of redclaw crayfish.

Corgos, A., Freire, J., Bernárdez, C., Fernández, L. and Verísimo, P.

Departamento de Bioloxia Animal, Bioloxia Vexetal e Ecoloxia, Universidade da Coruña, Campus da Zapateira s/n, E-15071 A Coruña, Spain

Timing and seasonality of the onset of maturity, gonadal maturation and mating in the spider crab Maja squinado: Relationships with habitat use and social structure

Sexual maturity, maturation and mating were monitored in the spider crab Maja squinado (Decapoda, Majidae) in shallow water of the Ría de A Coruña (Galicia, NW Spain) from 1997 to 1999. Juveniles inhabiting this area carried out a terminal moult to the morphometric adult phase from July to September, showing coordination among individuals, although females delayed one month the timing of this moult respect to males. Gonadal maturation in females started after the terminal moult, but males started to develop testicles several months before the terminal moult, after the pubertal moult to adolescent juveniles. During approx. 2 months after the onset of maturity, postpubertal adults remained in shallow waters, and after that they started a migration to deep waters. The reproductive status and body condition (hepatopancreas and leg muscle dry weights) were monitored for postpubertal adults along the migratory path to deep waters from September to December. Mating took place in deep habitats. Juveniles inhabited shallow (< 10 m) sandy bottoms and constituted aggregations that remained stable during long periods. After the terminal moult, postpubertal adults dispersed along the shallow habitat breaking down the aggregative structure and moved towards the deeper areas near the channel of the embayment.

Cox, Serena

School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand

Feeding behaviour of larval Jasus edwardsii.

Spiny lobsters form the basis of major fisheries in tropical to temperate areas of the major oceans of the world. The commercial interest in the aquaculture of members of this family is growing rapidly and is now facing some major constraints on further expansion. Overcoming these constraints will require a much more thorough understanding of the feeding behaviour and dietary requirements of the larvae stages than currently exists. The feeding behaviour, mouthparts and sensory structures of early stage Jasus edwardsii larvae has been investigated and described. Capture, manipulation and ingestion of prey items remained constant throughout stages 1-4, however the sensory structures became more developed with larval maturity. Mouthparts were also morphologically similar for each stage and processing ability was not significantly different. These results have significant implications for developing artificial diets for use in larval culture and incorporating desirable prey characteristics into the diet.

Crandall, K.A., Perez-Losada, M. and Carlson, M.

Department of Zoology and Monte L. Bean Museum, Brigham Young University, Provo, UT, USA

Phylogenetics and biogeography of the Southern Hemisphere freshwater crayfishes

Over 530 species of freshwater crayfishes are known to naturally inhabit areas of all continents except mainland Africa. Crayfishes are an interesting and imperative group to study because of the unusual distribution of species diversity (with two centers: southeast U.S. and Victoria, Australia), the ecological importance of crayfishes to freshwater ecosystems, and the fact that more than half of the known species of crayfish are considered threatened or endangered. Here we investigate the relationships among the genera within the Southern Hemisphere family Parastacidae. This family contains 14 genera distributed in Australia, New Zealand, Madagascar, and southern South America. Our study uses all the genera of the freshwater crayfishes as well as marine lobster outgroups and crayfishes from other families to provide an estimate of the evolutionary relationships among genera. Our estimates are based on nucleotide sequence data from both mitochondrial DNA (12S and 16S) and nuclear genes (18S and 28S), totaling ~6000 nucleotides of data. The resulting phylogeny is then used to test hypotheses of biogeography, morphological evolution, and conservation biology.

Cryer, M.

National Institute of Water & Atmospheric Research, Auckland, New Zealand

Developing a visual census technique for deep-water crustacean stock assessments

New Zealand scampi, Metanephrops challengeri, supports a 1000 t fishery. Stock assessment has been hampered by variable burrowing and emergence behaviour; research and commercial trawl catch rates are probably poor indices of abundance. Photographic surveying of burrows is being developed, based on a new deep-water digital camera. In a stratified survey of New Zealand's Bay of Plenty, 200-600 m depth, in February 2000, we estimated the average density of scampi burrow openings at about 0.10 m^–2 (12%). This means about 268 million burrow openings, only about one-third of the comparable estimate for a 1998 survey. The average density of visible scampi was 0.008 m^–2 (( 20%), about one-half of the estimate in 1998. The reasons for the differences between 1998 and 2000 surveys are unclear, but may be partly related to counting protocols. We are currently refining our protocols to provide for rigorous estimates of biomass using photography.

Cryer, M.¹, Hartill, B.¹ and O'Shea, S.²

¹National Institute of Water & Atmospheric Research, Auckland, New Zealand ²National Institute of Water & Atmospheric Research, Wellington, New Zealand

Effects of trawling on deep-water soft-sediment benthic communities

New Zealand scampi, Metanephrops challengeri, supports a 1000 t trawl fishery whose environmental effects are poorly understood. We combined data from the invertebrate bycatch of trawling with high-resolution tow-by-tow information on fishing effort since the start of the fishery. A suite of multivariate statistical analyses (linear modelling at community metric level, partial correlation at a species level, clustering at a station level, and ordination using nMDS and (partial) canonical correspondence analysis) showed that the composition of benthic assemblages vulnerable to trawling was predictable given a station's depth and fishing history. After excluding the effects of other variables, indices of fishing pressure explained 16-22% of variation in benthic community structure. Diversity increased with increasing depth but decreased with increasing fishing pressure. This work, undertaken at the scale of the fishery, suggests that there may be substantive effects of trawling deep-water soft-sediment benthic communities that should be considered in precautionary management.

Cuesta, J.A.¹, Schubart, C.D.² and Felder, D.L.¹

¹Department of Biology, University of Louisiana at Lafayette, Lafayette, USA ²Biologie 1, Universität Regensburg, 93040 Regensburg, Germany

Larval morphology and preliminary molecular systematics for the family Pinnotheridae de Haan, 1833, as evidence for a revised classification

The family Pinnotheridae is presently recognized as a group of 305 species, partitioned into 5 subfamilies: Anomalifrontinae, Asthenognathinae, Pinnotherinae, Pinnothereliinae and Xenophthalminae. Larval morphology is known for 53 species. In the present study, the zoeal and/or megalopal characters of these 53 species were compared to character states of larvae from possibly related groups among the Grapsoidea and Ocypodoidea. Pinnotherinae and Pinnotheriliinae share mouthpart setation patterns (close to Ocypodinae), but clearly differ in morphology of the antennae and telson. This supports recognition of separate familial status for each one, both of which are close to Ocypodidae. Differences in mouthpart setation, antennal development, and telson types distinguish larvae of Asthenognathus and Tritodynamia. These larval features suggest a close relationship of both genera with Varunidae (Grapsoidea), yet with clear differences between them that also support separate familial assignment. We suggest placement of Asthenognathus in Varunidae and establishment of a new family for Tritodynamia.

Cui, Z.X., Xiang, J.H. and Zhou, L.H.

The Experimental Marine Biology Laboratory, Institute of Oceanology, Chinese Academy of Sciences, Nanhai Road 7,Qingdao 266071, P. R. China

Triploidy induction with chemical shocks to Eriocheir sinensis.

Chemical treatment was employed to induce triploidy in Eriocheir sisnensis. The highest induction rate was 58.18%, with 6-DMAP(300 µmol/L) as inducer, 6 hour after ovulation, and the treatment time of 120 min; while with PA chemical as inducer, 5 hour after ovulation, and the treatment time of 240 min, the highest induction rate was 75.10%. In the chemical treatment experiments of PA chemical, 6-DMAP, CB, the highest induction rates were 77.51%, 51.70% and 49.10% respectively. In the treatment of pregnant crab with PA chemical, the pregnant crabs were normal after 4 hours' soaking, and even could recover after 10 hours soaking. The results showed that the highest induction rate was 73.14% during gastrula; 85.29% during zoea. Most seedlings died before megalopae owing to unsatisfactory culturing condition. For those did survive, 50.00% triploids were found during juvenile stage. In this study, a highly effective, cheap and safe inducer PA chemical (has been applied patent) was first used and triploid juvenile crabs were obtained for the first time.

Cunha, M.R.¹ and Sorbe, J.C.²

¹Centro das Zonas Costeiras e do Mar, Departamento de Biologia, Universidade de Aveiro, 3810-193 Aveiro, Portugal ²Laboratoire d’Océanographie Biologique, UMR 5805 (CNRS-UB1), 2, rue du Prof. Jolyet, 33120 Arcachon, France

A new collection of Crustacea from Lucky Strike: some notes on their ecology and spatial distribution within the hydrothermal vent field

The Lucky Strike hydrothermal vent field (Mid-Atlantic Ridge, 37º18'N, 32º16'W) and its surroundings were studied in August 2000, during the TTR-10 Cruise (Training Through Research - UNESCO/OIC), using a TV-assisted grab, a dredge and a gravity core (24, 8 and 1 samples, respectively). The macroinvertebrates were picked from the surface of the rocks and sorted from sieved sediments. Crustaceans occurred in 18 grab samples and accounted for about half of the identified taxa. One of the most interesting aspects of the collection is the high number of peracaridan species that are seldom collected during submersible dives and are also difficult to see and identify in video footages. The 667 specimens in the collection were ascribed to 41 different species (Cirripeda: 1; Amphipoda: 14, Isopoda: 13; Tanaidacea: 10; Decapoda: 3), including three probably new isopod species. Despite the high heterogeneity of the samples, a multivariate analysis (presence/absence data) identified two main clusters that can be related to the environmental gradient associated with the hydrothermal activity and geological settings within the vent field.

Dahms, H.-U.

Universität Oldenburg, FB 7, AG Zoosystematik und Morphologie, D-26111 Oldenburg, F.R.Germany

Burrowing crustacean nauplii: biology, ecology and evolution

Among Crustacean nauplii there is only one group of harpacticoid nauplii belonging to Stenhelia and Pseudostenhelia of Stenheliidae (Copepoda, Harpacticoida) constructing dwelling-tubes which do only consist of one opening serving as entrance and exit at the same time. They are skillful in lateral crawling locomotion, which they perform while stalking with the endopods of their second antennae. As for the correlation of a foreshortened body, lateral locomotion and refuge-seeking in a dwelling tube we hypothesize the following functional explanation: in order to reach or leave a narrow dwelling tube the fastest way, it is most suitable to enter and leave the tube sideways - in case backward locomotion is not possible. This way the evolution of lateral locomotion appears as a consequence of dwelling-tube construction.

Dahms, H.-U.

Universität Oldenburg, FB 7, AG Zoosystematik und Morphologie, D-26111 Oldenburg, F.R.Germany

The phylogenetic significance of the crustacean nauplius

Extant taxa like the Cephalocarida, Branchiopoda, Ostracoda, Mystacocarida, Copepoda, Cirripedia, Ascothoracida, Facetotecta, Euphausiacea and Penaeidea hatch from an egg as a free-living nauplius larva. Other crustaceans show an embryonic phase of development suggestive of a naupliar organization. The crustacean nauplius, as an organizational complex and phylotypic stage, is characterized by a remarkably conserved morphology. Besides structural and meristic differences, embryonic and postembryonic stages offer another set of characters, namely allometric differences and heterochrony for the reconstruction of phylogenetic relationships. From these character changes during ontogeny a gradient can be traced. Preadult characters suggestive of former character states, or that recapitulate those expressed in the course of ontogeny, are particularly valuable for the evaluation of phylogenetic character polarity. This morphology involving part of the genome of a group of organisms whose adults display remarkable adaptive radiation, has persisted with relatively minor modifications since Cambrian times.

Daniels, S.R., Stewart, B., Matthee, C., Cunningham, M. and Gouws, G.

Zoology Department, University of Stellenbosch, Private Bag X1, Matieland, 7602, South Africa

Phylogeny and biogeography of southern African freshwater crab species (Decapoda: Potamonautidae: Potamonautes) based on partial sequences from 12 and 16S RNA mt DNA genes, allozymes and morphology

The phylogeny of the southern African freshwater crab fauna was investigated using multiple data sets to, firstly, test the subgeneric divisions proposed by Bott (1955), secondly, to examine the relationships between hybridizing species pairs, and thirdly, to test the usefulness of freshwater crabs as zoogeographic indicators. Partial sequences from the 12 and 16SrRNA mt DNA genes were sequenced and analysed to explore the relationships among species. Generally, these two genes recovered the same tree topologies. Analyses of allozyme and morphological data further corroborated the placement of species. Bott's subgeneric divisions are paraphyletic and do not hold true. Secondly, most hybridizing species pairs appear to be closely related, and, thirdly, freshwater crabs are suitable organisms to test hypotheses regarding biogeographic relationships. These results are discussed in terms of contemporary and historic factors that are likely to have sculpted the present day distribution of species.

Daniels, S.R.¹, Gouws, G.¹, Stewart, B.¹ and Coke, M.²

¹Zoology Department, University of Stellenbosch, Private Bag X1, Matieland, 7602, South Africa ²KwaZulu-Natal Nature Conservation Services, P.O. Box 13053, Cascades, 3202, South Africa

Phylogeographic evidence for introgressive hybridization between two freshwater crab species (Decapoda: Potamonautidae: Potamonautes): implications for conservation and evolutionary significant units

Molecular data derived from allozymes and the 16SrRNA mitochondrial DNA gene were used to examine the degree of introgressive hybridization between populations of two freshwater crab species. Allozyme data derived from 16 loci revealed that three well-defined groups exist, including two groups formed by each of the putative species and a third group comprised of hybridizing populations. Congruent patterns were obtained from the DNA sequence data. Divergence between the two parental species and hybrid populations was equally high. The evidence supports the presence of an ancient introgressive hybrid zone between the two taxa that appears to be on a unique evolutionary trajectory. It has been previously argued that hybrid taxa are evolutionary insignificant. In the present study we explore the validity of hybrid taxa in the light of contemporary conservation dogma and argue for their conservation.

Daniels, S.R.¹, Stewart, B.A.¹ and Cook, P.A.²

¹Zoology Department, University of Stellenbosch, Stellenbosch, South Africa ²Zoology Department, University of Cape Town, Cape Town, South Africa

A congruent patterns of genetic variation as revealed by allozymes and mtDNA sequence analysis confirm the existence of high levels of gene flow in a burrowing freshwater crab

Five populations of the burrowing freshwater crab, Potamonautes calcaratus representing a total of 100 specimens, were collected from the Kruger Nation Park, South Africa. The population genetic structure of this species was investigated using both nuclear genetic markers (allozymes), and direct sequencing of a 610 base pair fragment the cytochrome oxidase 1(CO 1) subunit of the mitochondrial DNA. Electrophoresis of 21 allozyme loci revealed that populations were genetically similar (I = 0.984), with moderate differentiation (F(ST) = 0.12). Sequence data for 20 individuals revealed the presence of nine haplotypes, the distribution of which showed no geographic structuring. A ?ST of 0.43 was obtained among populations while within populations a ?ST of 0.62 was evident. The nucleotide diversity (?) was low and ranged from 0.00 to 0.007. Sequence divergence amongst populations ranged from 0.49% to 1.47%. Both genetic markers revealed weak population structuring, supporting the conclusion that high levels of gene flow are occurring among populations. These results provide evidence that allozyme and sequencing data may be congruent and that these independent markers can detect similar patterns of genetic differentiation. Results are discussed in light of contemporary factors that have been likely in sculpting the genetic structure.

Dauby, P., Nyssen, F. and De Broyer C.

Laboratory of Carcinology, Royal Belgian Institute of Natural Sciences, rue Vautier 29, B - 1000-Brussels, Belgium

Amphipods as food sources for higher trophic levels in the Southern Ocean

With nearly 900 different taxa, among which about 75% endemics, amphipods form one of the richest animal group of the Southern Ocean. They have colonized most habitats and exhibit very diverse life styles and trophic types. They moreover show a large size spectrum, with numerous giant species. Despite their importance in terms of biodiversity, very few is known about the role of amphipods in Antarctic trophodynamics. Based on an exhaustive survey of literature (>300 references), we tried to delineate their importance as potential food for higher trophic levels. About 200 different predators were recorded: 33 invertebrates (from 12 orders), 108 fishes (19 families), 48 birds (11 families), and 10 mammals. Using this vast dataset (total amount of citations close to 1500), an attempt was made to build up a small model, distinguishing between benthic and pelagic species of both amphipods and predators.

Davie, P.J.F.¹ and Dawson, E.W.²

¹Queensland Museum, PO Box 3300, South Brisbane, Queensland, 4101, Australia ²Museum of New Zealand, Te Papa Tongarewa, P O Box 467, Wellington, New Zealand

New species and new records of Lithodidae (Crustacea: Anomura) from Australia

Lithodids or "King Crabs" are relatively rare in Australian waters. Only three species have been previously identified, and all from deep waters (120 to 865 m) off the southeastern coast (Lithodes murrayi Henderson, 1888, Lithodes longispina Sakai, 1971, and Neolithodes brodiei Dawson & Yaldwyn, 1970). Apparently only L. murrayi Henderson, 1888, is moderately common, and none are fished commercially. Recent collections from tropical Australia have revealed the presence of a number of new records and new species. Material from the Coral Sea off north Queensland includes: Paralomis dofleini Balss, 1911; and Neolithodes nipponensis Sakai, 1971. Collections from off northern and northwestern Australia include: Acantholithus hystrix (De Haan, 1849) from the Timor Sea; and three new species from the North West Shelf, including a new species of Paralomis, and two new species of Lithodes. The nine Australian species comprise, a) two southern species confined to the Tasman Sea and sub-Antartic waters; b) three eastern Australian species that appear to belong to a more widely distributed western Pacific fauna; c) one northern species also a member of the western Pacific fauna; and d) three species indigenous to northwestern Australia.

Davie, P.J.F.¹ and Ng, N.K.²

¹Queensland Museum, PO Box 3300, South Brisbane, Queensland, 4101, Australia ²Department of Biological Sciences, National University of Singapore, Kent Ridge, Singapore 119260, Republic of Singapore

A review of Acmaeopleura Stimpson, 1858 (Crustacea: Brachyura: Grapsidae) with description of a new genus

Acmaeopleura Stimpson is reviewed and restricted to two species: A. parvula Stimpson, 1858, and A. rotunda Rathbun, 1909. The other three species attributed to this genus, A. balssi Shen, 1932, A. depressa Sakai, 1965, and A. toriumii Takeda, 1971, were discovered to all have third maxillipeds, and anterior sternal plates, strongly modified for filter feeding. All three appear to live commensally in the burrows of thalassinidean shrimps. The new genus is most closely allied to Gaetice Gistel, 1835, and the relationships of these two genera to other grapsoid crabs is discussed.

De Broyer C.¹, Scailteur Y.¹, Chapelle G.¹, Jazdzewski K.² and Rauschert M.³

¹Laboratory of Carcinology, Royal Belgian Institute of Natural Sciences, Rue Vautier 29, B - 1000 Brussels, Belgium ²Laboratory of Polar Biology and Oceanobiology, Department of Invertebrate Zoology and Hydrobiology, University of Lodz, 12/16 Banacha St., 90-237 Lodz, Poland ³Alfred-Wegener-Institut für Polar- und Meeresforschung, Forschungsstelle Postdam. Present address: Bruno-H.-Bürgel-Allee 31, D - 15732 Eichwalde, Germany

Habitat diversity of gammaridean amphipods in the Antarctic

Gammaridean amphipods appear to be ubiquitous in the Antarctic neritic communities where about 500 species have been recorded. By comparing benthic and pelagic catch data, ecomorphological traits and some ethological aquarium observations, an attempt was made to document the characteristic habitats and the microhabitats of the most common species. Six major macrohabitats (endobenthic, epibenthic with three levels, hyperbenthic, benthopelagic, pelagic and cryopelagic) and several symbiotic and endobiotic microhabitats (sponges, ascidians, hydrozoans and gorgonians) have been distinguished. Epibenthic species form the bulk of the fauna and are distributed among several strata formed by living sessile macrozoobenthos. Endobenthic species appear the second group in number, dwelling in the first centimetres of the sediment. Hyperbenthic (suprabenthic) habitat remains poorly documented. Few gammaridean species can be characterised as benthopelagic or pelagic and cryopelagic species have only been rarely recorded. The heterogeneous multi-strata environment of the benthos could account for the high species richness of the group in the Antarctic.

De Broyer, C.¹, Dauby, P.¹, Duchesne, P.A.¹, Jazdzewski, K.², Chapelle, G.¹, Jamar C.¹ and Weyland F.¹

¹Laboratoire de Carcinologie, Institut Royal des Sciences Naturelles de Belgique, 29 rue Vautier, B -1000 Brussels, Belgium ²University of Lodz, Laboratory of Polar Biology and Oceanobiology, Department of Invertebrate Zoology and Hydrobiology, 12/16 Banacha St., 90-237 Lodz, Poland

Biodiversity of the Southern Ocean: The "Ant'Phipoda" project

To assess amphipod biodiversity in the Antarctic coastal and shelf ecosystem (ACSE) and to evaluate their role in the ACSE, the Ant’Phipoda project was initiated in the framework of the SCAR EASIZ programme. .1 A Biodiversity Reference Centre for Antarctic Amphipods is under development at the Royal Belgian Institute of Natural Sciences in Brussels, including comprehensive databases on taxonomy, distribution and bio-ecology of the Antarctic amphipods and extensive reference collections and documentation. 2. An international network of 13 specialists (the "Antarctic Amphipodologist Network", AAN) was set up to undertake the taxonomical revision of the Antarctic fauna of gammaridean and caprellidean amphipods and to synthesize their biogeographical and ecological traits. 3. The elaboration of conventional and electronic identification tools for Antarctic amphipods has been undertaken by the AAN. 4. Studies on amphipod faunal -, habitat - and trophic type diversity are being conducted in selected benthic communities of the ACSE (Admiralty Bay in King George Island and the eastern Weddell Sea) to assess the potential roles of the habitat heterogeneity and trophic diversity in species diversification.

Desantis, S., Labate, M., D'Onghia, G., Maiorano, P., Cirillo, F. and Labate, G.M.

Department of Zoology, University of Bari, Via E.Orabona, 4 - 70125 Bari - Italy

Emi-spermatophore and spermatophore sperm surface glycoproteins in giant red shrimp Aristaeomorpha foliacea.

The sperm surface is involved in intercellular process of fertilization, thus the glycoproteins of sperm plasma membrane seem to be of critical importance in the fertilizing ability. Since it is known that mating can occurs a few months before ovulation, the aim of this study is to investigate the sperm surface glycoproteins using a series of lectin and prelectin methods in hemi-spermatophore and spermatophore spermatozoa in order to determinate the glycoprotein pattern associated with sperm fertilizing ability.

Diele, K.

Centre for Tropical Marine Ecology (ZMT), Fahrenheitstr. 6, 28359 Bremen, Germany

Timing of reproduction and larval dispersion of the mangrove crab Ucides cordatus cordatus (Ocypodidae) in the Caeté Estuary, North Brazil

Mating activities of U. cordatus cordatus and the abundance of larvae in a tidal channel of the Caeté Estuary were monitored from 1997 to 1999. Reproduction occurred in the rainy season between December and June and followed a lunar rhythm. Synchronised mate-searching and mating events took place during four days after new moon, with a peak in January or February. Females spawned at the following new moon in the inundated mangrove forest within four days at high tide. Subsequent ebb currents transported the larvae to tidal channels, where up to 225000 indiv.m-3 were recorded. Larval export to coastal waters was indicated by rapidly decreasing zoeal numbers in the estuary towards low tide. The absence of later stage zoeae in the tidal channel suggests that development to postlarval stage occurred offshore. Megalopae re-invaded the estuary within distinct recruitment phases of up to 13 days, again with a peak near new moon.

Diele, K.

Centre for Tropical Marine Ecology (ZMT), Fahrenheitstr. 6, 28359 Bremen, Germany

Biology of the exploited mangrove crab Ucides cordatus cordatus (Ocypodidae) in the Caeté Estuary, North Brazil

Reproduction, growth and population structure of U. cordatus cordatus was investigated in the Caeté Estuary, where the species sustains more than 40% of the rural households. Reproduction was confined to the rainy season and one cycle from mating to post-larval occurrence encompassed six to eight weeks. Growth increment studies and moulting frequency observations indicated that the species is slow growing. Market-sized males with a carapace width (CW) of 6.5 cm have an estimated age of 6.5 to 8 years. Despite the slow growth and an exploitation since 40 years large males were still abundant: an average of 40% of all males in commercial capture areas had a CW of 6.5 cm or larger. Mean CW of commercially landed crabs was 7.3 cm, with the largest male measuring 9.3 cm. Beside the size and sex selective fishery a mosaic of natural refugia has most likely prevented a severe overfishing until today.

dos Santos, A.¹ and Gonzáles-Gordillo, J.I.²

¹Instituto de Investigação das Pescas e do Mar (IPIMAR). Av. de Brasília, s/n. 1449-006 Lisboa, Portugal ²Departamento de Biologia (CZCM). Universidade de Aveiro. 3810-193 Aveiro. Portugal

An illustrated key for the identification of zoeal stages of Pleocyemata larvae (Crustacea, Decapoda), from the Southwestern European coast

The identification of zoeal stages of decapod larvae in plankton is not easy, principally because morphological characteristics change from one phase to another, and also, there is a lack of available larval descriptions for many species. An illustrated key for the identification of zoeal stages of decapod larvae from the Southwestern European coast is based on observation from our own larval planktonic samples and from previously published larval descriptions. This key includes 70 taxa, the majority of them separated to species and genus level. The characteristics used to make this key are, when possible, external morphological ones and easy to see with a stereomicroscope. In addition, distinctive features of taxa are illustrated to clarify and facilitate the identification of specimens.

dos Santos, A.¹ and Paula, J.²

¹Instituto de Investigação das Pescas e do Mar (IPIMAR), Av. de Brasília, s/n. 1449-006 Lisboa, Portugal ²Laboratório Marítimo da Guia - IMAR, Estrada do Guincho, 2750-642 Cascais, Portugal

Redescription of the larval stages of Upobebia pusilla (Petagna, 1792) (Thalassinidea, Upogebiidae) reared under laboratory conditions

The complete larval development is described and illustrated for Upogebia pusilla (Petagna) reared under laboratory conditions. The development consists of four zoeal stages and one megalop. The morphological features of the zoeal and megalop stages of U.pusilla are compared with of other species of Upogebia, and a key of the known zoeal stages of the genus is given.

Dunbar, S.G.¹, Coates, M.¹ and Kay, A.²

¹School of Biological and Environmental Sciences, Central Queensland University, Rockhampton, Queensland, 4702, Australia ²Queensland Parks and Wildlife Service, PO Box 3130, Rockhampton Shopping Fair, Queensland, 4701, Australia

Marine hermit crabs as indicators of freshwater inundation on tropical shores

The marine hermit crabs, Clibanarius taeniatus (H. Milne Edwards, 1848) and Clibanarius virescens (Krauss, 1843) are common rocky intertidal species along the coast of Queensland, Australia. A survey from Redcliffe (23 15.5'S, 150 50.0'E) to Cape Kimberley (16 16.7'S, 145 29.1'E), showed that C. virescens tends to be more dominant on open coasts, while C. taeniatus tends to be more abundant in areas influenced by freshwater. Repeated sampling at selected sites revealed that a site with no freshwater influence maintained a low percentage of C. taeniatus and high percentage of C. virescens, while at a site influenced by regular, low level freshwater runoff, the percentage of C. taeniatus remained high. Laboratory experiments in dilute (22%) seawater at 15, 25 and 35°C over an extended period showed that C. taeniatus survived significantly (P<0.01) longer than C. virescens. In a low salinity, estuarine environment C. taeniatus survived significantly (P<0.001) better than C. virescens. These findings suggest that these two species can serve as a convenient indicator system for the detection of freshwater inundation on coastal environments.

Dworschak, P.C.

Dritte Zoologische Abteilung, Naturhistorisches Museum in Wien, Burgring 7, A-1014 Wien, Austria

Biology of Mediterranean and Caribbean Thalassinidea (Decapoda)

Burrow construction is a characteristic of several crustacean groups. Among those, the most complex and extensive burrow systems are found within the Thalassinidea. This group of decapods comprises some 520+ species in currently 11 families and 80+ genera. They live predominantly in very shallow waters, where they often occur in high densities and influence the whole sedimentology and geochemistry of the seabed. In this contribution I present results of studies on the biology of several Mediterranean (Upogebia pusilla, U. tipica, Callianassa tyrrhena, C. candida, Jaxea nocturna) and Caribbean (Axiopsis serratifrons, Neocallichirus grandimana, Glypturus acanthochirus, Corallianassa longiventris) species. Of special interest is the occurrence of debris-filled chambers in the burrows of two callianassid species. The possible role of this introduced plant material for the nutrition of the shrimps is discussed.

El-Rashidy, Hoda and Boxshall, Geoff

The Natural History Museum, London SW7 5BD, UK

The Ergasilidae - the exception to Fahrenholz's rule

Parasitic copepods, like most parasites, tend to conform to Fahrenholz's rule - that there is generally marked parallelism between the phylogeny of a group of parasite species and that of their hosts. The Eudactylinidae is a good example of such a basically coevolutionary history, and one which also shows occasional colonization events. The adult females of the family Ergasilidae are parasitic, typically on fishes, but preliminary studies of their phylogenetic and host relationships suggest a difference balance between coevolutionary and colonization events. Analysis of records of ergasilids on grey mullets (Mugilidae) leads us to infer multiple colonizations, and repeated switching between host taxa. Excluding the large but polyphyletic type genus Ergasilus, we identify at least ten independent colonizations of mugilids by ergasilids. Despite the need for revisionary study, it is possible to recognise several other lineages within Ergasilus that also utilize mugilids. Factors generating this unusual host-parasite relationship are discussed.

Emmerson, W.

Dept of Zoology, University of Transkei, E. Cape South Africa

On the occurrence of a population of the arboreal mangrove crab Sesarma leptosoma from Mgazana, a sub-tropical/ warm temperate mangrove estuary in Transkei, South Africa

To date the arboreal searmid Sesarma leptosoma has only been recorded fro tropical Indian Ocean mangrove systems such as Gazi Bay, Kenya. However, recently a population has been found out of the tropics at Mgazana (31 42'S, 29 25'E). Here they are found almost exclusively associated with Rhizophora and Bruguiera, and not Avicennia. Here they exhibit diurnal migration rhythms between the canopy and roots similar to that reported for Kenya (Vannini et al, 1997). Females breed during March in late summer similar to other crab species in this southerly system (Emmerson, 1994) Local communities harvest both Bruguiera and Rhizophora selectively for building poles as they are straight and termite resistent, so although this species has only recently been discovered, it is already threatened through habitat destruction. Estimates of the harvested area relative to total standing stock are given to assess the effect deforestation may have on crab population size and sustainabilty.

Emmerson, W.

Dept of Zoology, University of Transkei, E. Cape South Africa

Growth and recruitment of Uca vocans at Mgazana a warm temperate mangrove estuary in the East Cape South Africa

A population of Uca vocans was sampled for two years in the Mgazana estuary, a southerly mangrove system on the south-east coast of South Africa. As they were confined to an area on a sandbank near the mouth, only one site was sampled once a month. Crabs were identified, measured and sexed and their size frequencies plotted. Cohort analysis was used to show growth progression. Gravid females are known to have a spawning peak from December to March (Emmerson, 1994) which is followed by offshore development of zoeae and megalopae. First crab stages then recruit back into the estuary in April and a strong cohort of juvenile crabs appear on the banks from May to July. The growth of these cohorts was then monitored showing that they reach early adult stage after a year and full maturity after two years, when in turn can spawn and complete the life cycle of a generation.

Evans, L.H., Senaratana, M. and Fotedar, S.

Aquatic Science Research Unit, Muresk Institute of Agriculture, Curtin University of Technology, GPO Box U1987, Perth, WA 6845, Australia

Host defence reactions and hemolymph assays in spiny lobsters, Panulirus cygnus, with shell lesions

Histopathological features, immune parameters and hemolymph pH levels in lobsters with tail blisters and tail rot were compared to those of healthy lobsters without lesions in two separate trials. In Trial 1, the lobsters were subjected to a confinement stress (storage overnight submerged in a basket) while Trial 2 lobsters were allowed to free-range in the factory tank overnight. Trial 1 healthy lobsters (n=5) had significantly lower levels of circulating hemocytes, higher prevalence of animals with impaired clotting and a smaller decrease in hemolymph pH following transport to the laboratory in air compared to lobsters with shell lesions (n=7). No lobsters in the second trial exhibited impaired clotting and the immune parameters and hemolymph pH levels were similar in both groups. It was concluded that confinement stress has an adverse effect on health status in P. cygnus and that healthy lobsters had a higher stress resistance than lobsters with shell lesions.

Evans, L.H.¹, Tsvetnenko, E.¹, Jussila, J.² and Fotedar, S.¹

¹Aquatic Science Research Unit, Muresk Institute of Agriculture, Curtin University of Technology, GPO Box U1987, Perth, WA 6845, Australia ²Institute of Applied Biotechnology, University of Kuopio. Kuopio, Suomi-Finland

Health status assessment in spiny lobsters: Comparative study of various immune system and other health parameters in Panulirus cygnus and Jasus edwardsii.

Health status was assessed using hemolymph immune assays (total circulating hemocytes (THC); proportion of circulating granular cells; clotting time) and other health parameters (prevalence of bacteremia; hemocytic reactions in body tissues) in healthy and moribund lobsters. The moribund lobsters were obtained following simulated live transport in air and subsequent storage for 24-48 hr in a factory tank (Panulirus cygnus) or overnight in a cold room (Jasus edwardsii). Morbidity was determined by observation of absence of tail flapping, loss of muscle tone and reduced appendage movement. The level of circulating granular cells was significantly reduced in moribund lobsters and this reduction was correlated with the presence of systemic hemocytic reactions in body organs. Differing patterns of variation in THC were observed, with moribund P. cygnus showing a marked reduction in THC and J. edwardsii showing increased THC levels. Clotting time was prolonged in moribund P. cygnus compared to matching, healthy controls. Bacteremia was higher in moribund lobsters in both species.

Factor, J.R.

Division of Natural Sciences, Purchase College, State University of New York, Purchase, New York, 10577, USA

The role of fixed phagocytes in decapod crustacean defenses

Fixed phagocytes of decapod crustaceans are tissue-bound defensive cells that together constitute an important defensive organ. First recognized in the early twentieth century by Cuénot as "l'organe phagocytaire", his work appears to have been forgotten for many years. Circulating phagocytic hemocytes have received the primary attention as the mechanism of cell-mediated immunity, yet the fixed phagocytes must be included in our consideration of crustacean defenses. Typically, there is a large population of fixed phagocytes in the digestive gland (hepatopancreas). The phagocytic cells are organized as nodules, rosettes, or a layer surrounding branches of the hepatic artery, which lie in the hemal sinuses and are bathed in circulating hemolymph as it percolates through the digestive gland. Foreign particles collect under an apical perforated membrane prior to phagocytic uptake. The role played by the fixed phagocytes in the removal of foreign particles from the blood will be explored.

Farley, Gregory S.

Department of Biological Science, The Florida State University, Tallahassee, FL, USA

The evolution of commensalism in pea crabs (Brachyura: Pinnotheridae)

Study of symbiotic interactions has traditionally focused on mutualisms and parasitisms. Despite its frequency in nature, commensalism has received little attention from biologists, and the evolutionary origin and persistence of commensalism remain unexplored. Most pea crabs (Brachyura: Pinnotheridae) are obligate ectosymbionts; many are commensals, some are parasites, and some are not symbiotic. I infer a molecular phylogeny for several genera of pinnotherid crabs; I map the symbiotic strategies of each taxon onto these phylogenies and estimate ancestral character states; and I use these estimates to test several hypotheses about the evolutionary origin and trajectory of commensalism. Specifically, I test the hypotheses that A) commensalism may arise from antagonistic interactions, such as parasitism, by a loss of virulence in a parasitic member of a clade, and B) commensalism may arise from noninteractions and either i) persist through evolutionary time, or ii) give rise to other types of symbioses.

Farrelly, C.A. and Greenaway, P.

School of Biological Science, University of New South Wales, Sydney, Australia

A novel breathing organ in terrestrial hermit crabs: the abdominal lung

Most land crabs, including Birgus latro have developed branchiostegal lungs for aerial gas exchange. However, in the shell-carrying coenobitids, the branchiostegites have been restricted by need to retract into the shell and are thus narrow with a relatively small surface area and the internal space is occupied predominantly by the gills. In consequence, coenobitids have developed an alternative and supplementary respiratory site on the dorsal surface of the abdomen, which is protected by the shell. The dorsal cuticle of the abdomen is very thin and transparent and is formed into numerous tiny folds that greatly increase the surface area. Corrosion casts show this site to be highly vascular, with a complex network of lateral vessels supplied by paired longitudinal veins. Sections through this tissue also show that a very thin cuticle and epithelium line the exchange lacunae, producing an efficient lung with a blood/gas diffusion distance of 300-500nm.

Fenwick, G. D.

National Institute of Water & Atmosphere, P.O. Box 8602, Christchurch, New Zealand

Role of phreatic isopods in maintaining groundwater quality

Field measurements and experiments showed that fine particulate and dissolved organic carbon entering the Canterbury groundwater (10 m below ground) is incorporated into layers on inorganic surfaces. Phreatoicus typicus, a large phreatic isopod, is particularly numerous downstream of surface sources of organic enrichment. In lab experiments using 14C-glucose, P. typicus assimilated much less organic carbon from layers on gravel surfaces than from layers on clay particles. Gut analyses confirmed that P. typicus ingests only clay-sized particles, as well as ingesting and digesting bacteria. Also, its mouthparts are ill equipped for scraping and shredding. These features, along with its ponderous locomotion, indicate that P. typicus is a microphagous feeder. Estimates of population densities and feeding rates suggest that P. typicus removes significant amounts of organic carbon within Canterbury alluvial aquifers. Thus, it maintains the porosity of the aquifer and the quality of groundwater through contaminant removal.

Fernández, L.¹, Verísimo, P.¹, Bernárdez, C.¹, Corgos, A.,¹ Freire, J.¹ and Fidalgo, P.²

¹Departamento de Bioloxía Animal, Bioloxía Vexetal e Ecoloxía, Universidade da Coruña, Campus da Zapateira s/n, E-15071 A Coruña, Spain ²Departamento de Bioloxía Celular e Molecular, Universidade da Coruña,

Campus da Zapateira s/n, E-15071 A Coruña, Spain

Energetic and biochemical changes during gonadal maturation and embryonic development in the spider crab Maja squinado (Decapoda: Majidae)

Females of the spider crab, Maja squinado, spawn 2 or 3 times a year in the Ría de Arousa (Galicia, NW Spain). During the embryonic development gonads maturate to be ready for the next spawn, and the females have to attain the energetic and material resources (mainly lipids and proteins) to build the yolk of the ovocites. Hepatopancreas is a key tissue in the management of energetic resources involved in the reproduction of decapods. In this paper, we show the preliminary results on the energetic content and the biochemical composition of the eggs, gonads and hepatopancreas of Maja squinado in different gonadal maturation and embrionic development stages. A total of 50 ovigerous females were collected in the Ría de Arousa, during the spawning period. Biochemical analysis of freeze-dried hepatopancreas, gonad and eggs samples were carried out. Lipid and energetic contents were much higher in hepatopancreas than in gonad and eggs, which showed higher porcentages of proteins. Gonads and embryos showed significant variations in their biochemical composition and energetic content during development. Biochemical composition of hepatopancreas remained similar in different phases of gonadal maturation.

Ferreira, A.C., Sankarankutty, C, Cunha, I.M.C. da and Duarte, F.T.

Museu do Mar "Onofre Lopes, Universidade Federal do Rio Grande do Norte, Natal, Brazil

Recent additions to the carcinological fauna (Crustácea : Decapoda) of the northeast of Brazil

A comprehensive knowledge on the decapod fauna of the littoral region of the northeast of Brazil is now available ( Coelho, 1967/69; 1972; Coelho & Ramos, 1972; Coelho et al.1980, 1983, 1986; Coelho & Ramos-Porto, 1981; Coelho & Torres, 1989 & 1991/91; Fausto-Filho, 1966,1967,1968,1970,1975; Sankarankutty et al., 1991). However, a survey of the estuaries of the State of Rio Grande do Norte (Sankarankutty & Manning, 1997 ; Ferreira & Sankarankutty, 1998; Sankarankutty et al.,1998, 1999; Sankarankutty & Ferreira 2000) demonstrated that the sublittoral region offers opportunity to find new and unrecorded species. Discovery of two species of spider crabs (Sankarankutty et al.,1998) and exploitable population of Chaceon fenneri Manning & Holthuis (Sankarankutty et al., in press) from the offshore region of the northeast of Brazil confirms that sublittoral region of the coastal waters remains largely unexplored. Treated here are the new species and unrecorded species from the northeast of Brazil..

Fiedler, G.C.

Sesoko Station, Tropical Biosphere Research Center, University of the Ryukyus, Okinawa, Japan

Hermaphrodites & parasites: A sordid tale of shrimp sex and isopod manipulation

In decapod crustaceans, simultaneous hermaphroditism has only been demonstrated in the hippolytid genus, Lysmata. Here I report the reproductive patterns of three Lysmata species occurring in Hawaii, L. anchisteus, L. trisetacea, and L. ternatensis, and assess the impact of an abdominal 'castrator' parasite (Bopyridae) on sexual function. Sexual function was observed in isolated shrimp pairs and preserved materials. I examined the ability to spawn and/or fertilize eggs, as well as external sex characteristics and reproductive histology. All species displayed the same general sexual pattern: individuals function first as males and later in life as simultaneous hermaphrodites. Parasites were observed in field collections of L. ternatensis (20%) and L. trisetacea (10-33%), but not L. anchisteus. Parasites effectively inhibited only female reproductive ability in all hosts. This may be unique among caridean hosts, and suggests abdominal bopyrids may have played an important role in the evolution of the unique Lysmata sexual system.

Flores, A.A.V., Cruz, J. and Paula, J.

Laboratório Marítimo da Guia - Faculdade de Ciências da Universidade de Lisboa, Cascais, Portugal

Scales of spatial variability and temporal patterns of brachyuran settlement along a rocky coast in Central Portugal

Square mesh traps (0.5 X 0.5m) placed under natural boulder cover were used for sampling brachyuran megalopae at rocky shores within the Cascais area, Central Portugal. Megalopae of all species recorded at the study area were obtained using these collectors. We used the data on Pachygrapsus marmoratus to test for significant spatial scales of settlement variablility, i.e. hundreds, tens and unit meters, using a nested analysis of variance design. Significant contrast was found between areas 1 km appart, while no differences were detected at lower scales. Temporal settlement patterns were examined for P. marmoratus and Xantho incisus. For the former species, spectral analysis of data from two consecutive years revealed that both lunar and semilunar cycles might occur, probably depending on prevailing wind direction and intensity. In the latter, a single settlement season was examined during which fortnight cycles were detected. Potential mechanisms for onshore transport of larvae are discussed.

Forest, Jacques¹ and McLay, Colin L.²

¹Laboratoire de Zoology (Arthropodes), Museum national d'Histoire naturelle, 61 Rue Buffon, Paris, 05, France ²Department of Zoology, University of Canterbury, Christchurch, PB 4800, New Zealand

The biogeography and bathymetric distribution of New Zealand hermit crabs (Crustacea: Anomura: Paguridea)

According to the recent publication of Forest et al, 2000, there are 60 species of hermit crabs living in the New Zealand region, including the Kermadec Islands. All the major families of the Paguridea are represented: Pylochelidae (7 species), Diogenidae (11), Paguridae (33), and Parapaguridae (9). There are two distinct faunas, one belonging to the subtropical Kermadec Islands and the other belonging to the area of New Zealand itself. Only five species are shared. A feature of the fauna is the high level of endemism, especially in the Diogenidae where it reaches 73%. If we include New Caledonia and Eastern Australia, then 86% of the Pylochelidae and 84% of the Paguridae are endemic to that region. The level of endemism is higher for New Zealand (60%) than for the Kermadecs (35%). In relation to depth, endemism in the intertidal zone is 67%, rising to 85% by 50 m, and remaining above 60% down to 200 m. Species living at greater depths tend not to be endemic. By virtue of their deeper habitat, the Pylochelidae (which retain many ancestral characters) and Parapaguridae contribute very little to the list of endemics. Large eggs are a family characteristic for the pylochelids, but are a generic character for the diogenids. For the most part small eggs are a family characteristic of the Paguridae. Hypotheses about the speciation of the hermit crabs in this region are discussed. We argue that different mechanisms are important for the speciation of the Diogenidae on the one hand and the Paguridae on the other.

Fortunato, C., Falcioni, V. and Sbordoni, V.

Dipartimento di Biologia, Università di Roma "Tor Vergata", Roma, Italy

Genetic structure of the rockpool prawn (Palaemon elegans) as a potential marine pollution marker

The genetic structure of the rockpool prawn (Palaemon elegans) was analyzed in thirty-two populations sampled along the Italian coasts in sites at different degree of environmental stress. The analysis of allozymes encoded by twenty-five loci showed a high gene flow between all populations, as expected from the high dispersal ability of the larval stage. Pattern of genetic variation was not correlated to geographic distance. Multivariate analyses clearly assigned P.elegans populations to different groups on the basis of levels of marine pollution. At seven loci genetic variation was attributable to direct or indirect selection. In particular, at some of these loci, allele and genotype frequencies showed statistically significant correlation with Hg and Cd concentrations in coastal marine sediments. This paper opens interesting prospects for the use of allozymes in Palaemon elegans as biomarkers of marine pollution.

Fotedar, R. and Whisson, G.J.

Aquatic Science Research Unit, Muresk Institute of Agriculture, Curtin University of Technology, Perth, WA, Australia

Condition indices and biochemical composition of marron (Cherax tenuimanus) from selected sites in southern Western Australia - a comparative study

Wet and dry organosomatic indices combined with proximate composition of hepatopancreas and tail muscle have been used to determine the health status of Western Australian marron (Cherax tenuimanus). While some data is available on condition indices of freshwater crayfish from different culture environments, no such data is available from populations in the South-West. Data collected during a Natural Heritage Trust funded project will be presented detailing direct and indirect impacts of anthropogenic activities on marron condition indices and biochemical composition. In addition, comparative data indicating significant differences between "natural" marron populations and intensively cultured animals will be discussed, assisting to benchmark the health status of native populations of marron from selected waterbodies in south-western Australia.

Fotedar, S. and Evans, L.H.

Aquatic Science Research Unit, Muresk Institute of Agriculture, Curtin University of Technology, GPO Box U1987, Perth, Western Australia 6845

Clotting time assays in Western rock lobster, Panulirus cygnus.

The hemolymph of lobsters clots on contact with air. The time taken for clot formation can be measured by a simple technique. A known volume of hemolymph is drawn into a hematocrit tube, the tube continuously inverted until no further movement of hemolymph could be detected visually and the time noted. In some cases no clot formation was observed in the 2 minute observation period. Such cases were recorded as 'no clots'. The clotting times were expressed as ranks (0= 0-10 secs to 9= > 90 secs) to provide numerical data accounting for cases where no clots were observed after 90 seconds. The reproducibility of the clotting time assay was studied by two observers using the same hemolymph sample. Clotting times for lobsters held in factory tanks for 1-8 days were assessed. The influences of various factors such as moult stage, starvation and handling etc were studied. The normal range of hemolymph clotting time for factory stored lobsters ranged from 25-49secs (ranks 2-4). The clotting time were significantly higher (P< 0.05) after 7-8 days holding in factory tanks (mean ranks ranged from 3.0 0.21(n = 12) to 6.10.71 (n=10)). A high level of precision was noted in the reproducibility assay ((r2 =0.89, n= 10) and (r2 = 0.77, n=12)). The influence of various factors such as moult stage, starvation, handling etc on clotting times will be presented. The significance of these findings in immune studies will be discussed.

Fransen, C.H.J.M.

Nationaal Natuurhistorisch Museum, Leiden, The Netherlands

Phylogeny, historical biogeography and historical ecology of pontoniine shrimps associated with ascidians and molluscs

The Pontoniinae form the most radiated subfamily of shrimps in the marine environment with about 420 recognised species of which most have been recorded in the Indo-West Pacific. These shrimps occur in tropical and subtropical waters around the world usually living in association with other invertebrates. Fifteen of the more than 80 genera in the subfamily comprise species living in association with solitary ascidians or bivalve molluscs. The phylogeny of these genera has been analysed using PAUP and McClade software. Two genera occur in the Atlantic and East Pacific, the others are distributed in the Indo-West Pacific. Most genera have a relatively small host-range with the shrimps species associating with host within one genus or one family. Several introductions in other host-groups can be observed from the analysis.

Fransozo, A., Bertini, G. and Marques, F.P.L.

NEBECC ( Group of Studies on Crustacean Biology, Ecology and Culture) Departamento de Zoologia, IBB, UNESP, Botucatu (SP), Brazil

Larval development of Notolopas brasiliensis Miers, 1886 (Decapoda: Majidae: Pisinae) reared in the laboratory

The larval development of the spider crab Notolopas brasiliensis Miers, 1886 is described from specimens reared in the laboratory and provide a first description of zoeal larvae in this genus. Larvae were obtained from ovigerous females collected in the non-consolidated sublittoral using two double-rig trawling nets. The larvae culture was carried out in a climatic room with constant temperature (24+1 C) and salinity (34.5%). The larvae were maintained individually and the food consisted of Artemia nauplii. The zoea and megalopa were fixed in 10% formalin and then transferred to a misture (1:1) of 70% ethyl alcohol and glycerin; 15 specimens for each stage were dissected for detailed descriptions The larval development of N. brasiliensis consists of two zoeal stages and a megalopa. The morphological features found for N. brasiliensis zoea confirm its status in Pisinae, mainly concerning to the maxilla setation. Additionally, a comparison with previously studied majid species occurring in the Southwestern Atlantic is provided.

Fransozo, A.^{1, 2}, Costa, R.C.^{1, 2} and Mantelatto, F.L.M.^{1, 3}

¹NEBECC (Group of Studies on Crustacean Biology, Ecology and Culture) ²Departamento de Zoologia, IBB, UNESP, Botucatu (SP), Brasil ³Departamento de Biologia, FFCL, USP Ribeirão Preto (SP), Brazil

Biodiversity of marine shrimps (Penaeidea and Caridea) at the northern coast of São Paulo state, Brazil

The goal of this work was to analyze the biological diversity of Penaeidea and Caridea that occur in the northern sublittoral of São Paulo state. This investigation is part of a wide project on Benthic Marine Biodiversity, which aims to contribute for a better assessment of local marine invertebrates. The samplings have been conducted on the non-consolidated sublittoral using two double-rig trawling nets. Twenty four marine shrimps species, belonging to eight families have been found. Among the Dendrobranchiata, the Penaeidae is the most representative with 6 species, followed by Sicyoniidae(4); Solenoceridae(1) and Sergestidae(2). Carideans have been represented by Palaemonidae (3); Alpheidae (6); Ogyrididae(1) and Hippolitydae(1). The Penaeidea and Caridea taxocoenosis were dominated, respectively, by Xiphopenaeus kroyeri and Exhippolysmata oplophoroides. The distribution and abundance of these shrimps are markedly associated to hydrological features. This region can be considered as an important site to the establishment and development of diverse marine shrimp populations.

Gaddes S.W. and Sumpton W.D.

Department of Primary Industries, Queensland, Australia

Distribution of barnacle symbionts of the crab Portunus pelagicus in the Moreton Bay region, Eastern Australia

Blue swimmer crabs (Portunus pelagicus) collected in three areas around Moreton Bay, Australia were examined for the presence of barnacle symbionts on their gills and carapace. A total of 952 crabs were inspected with 72,212 barnacles found. The overall infestation rate was 92%. The mean number of barnacles per carapace and gill chamber were 2.35 and 71.1 respectively. Barnacle infestation was found to differ significantly by area, season and sex with the deeper offshore areas exhibiting the highest barnacle abundances. The distribution within the hosts showed barnacles were more likely to be distributed in areas closer to the inhalent aperture. Highest abundances were found on the proximal segment of the hypobranchial side of gills 3, 4 and 5. Host molt stage and parasitism by Sacculina granifera were also found to affect the abundance of barnacle symbionts in some areas.

Garcia, R.B. and Mantelatto, F.L.M.

Departamento de Biologia, FFCLRP, Universidade de São Paulo, Ribeirão Preto, SP, Brazil

Population structure and reproductive period of the hermit crab Paguristes erythrops (Diogenidae) from Anchieta Island, Brazil

The population of Paguristes erythrops was studied based on seasonal abundance, size frequency distribution, sex-ratio and reproductive period (percentage of ovigerous females). Specimens were collected monthly by scuba diving methods in the infralittoral area of Anchieta Island. A total of 543 individuals were analyzed. Animal size (minimum; maximum; mean shield length sd, respectively) was 1.7; 11.8; 5.95 2.18 mm for males, 1.7; 10.3; 4.51 1.64 mm for non-ovigerous females and 3.2; 7.8; 4.90 0.88 mm for ovigerous females. The sex-ratio was 0.91:1 in favor of females. Sexual dimorphism was recorded by the presence of males in the largest size classes. The absence of ovigerous females during winter months (June to August) and their high incidence from January to March, indicated discontinuity in reproductive cycle. Further studies on gonad development and juvenile recruitment are in progress to a better understanding of this population dynamics.

Garm, A.

Department of Zoomorphology, University of Copenhagen, Denmark

Functional morphology of decapod setae

Setae play an important role in the biology of crustaceans since they constitute a major part of their sensory system a side from having a wide variety of mechano-effector functions. This has lead to many functional interpretations of setae but most are based on morphology alone, which is problematic. Especially the sensory modality is neglected in such studies. In the presented project one species from each of eight major decapod taxa is studied, Dendrobranchiata, Stenopodida, Carida, Astacida, Palinura, Thalassinidea, Anomura and Brachyura. I chose to study the mouthparts since they have the greatest diversity of setae and are easily observed in vivo. SEM and TEM are used to see if there is a correlation between external morphology and internal morphology. Observations of functions are achieved by macro-video recordings of the setae on the mouthparts and by electro-physiological recordings from the setal nerves. Preliminary results mostly from the morphology will be shown.

Garm, A.

Department of Zoomorphology, University of Copenhagen, Denmark

Mechano-effectory functions of decapod setae revealed by macro-video recordings

Setae have a wide variety of functions and many of these functions are mechano-effectory. These functions are largely dependent on the external morphology of the setae and what are presented here are results of a study on the functional morphology of decapod setae. The external morphology is studied by SEM and the mechano-effectory functions are studied by macro-video equipment. The setae on the mouthparts are chosen as study objects, since their usage is easy to provoke. One species from each of the eight subtaxa of Decapoda (Dendrobranchiata, Stenopodida, Carida, Astacida, Palinura, Thalassinidea, Anomura and Brachyura) were used as study animals. They were feed various types of food and the mouthparts were filmed while eating. Another very important function of the mouthparts is grooming especially of the antennae and the setae involved in this behaviour were also filmed. Video-recordings will be shown and compared with results from the SEM examinations.

Gerken, S.

Biology Department, Bates College, 44 Campus Ave., Lewiston, ME 04240, USA

The first phylogenetic analysis of the Gynodiastylidae

A computer assisted cladistic analysis of the Gynodiastylidae (Crustacea: Cumacea) was undertaken to determine if the family is monophyletic and elucidate relationships among the genera in the family. Morphological information was obtained from the literature, and 18 characters were scored for 14 taxa (12 ingroup, 2 outgroup) at the generic level. Monophyly of the Gynodiastylidae is supported in all trees, and two distinct subclades are supported in all trees, a Dicoides subclade (Dicoides, Paradicoides, Zimmeriana, Pseudozimmeriana), and a Gynodiastylis sensu stricto subclade (Gynodiastylis, Axiogynodiastylis, Haliana). The relationships of the plesiomorphic genera (Eogynodiastylis, Litogynodiastylis, Sheardia) are not well resolved, suggesting a need for development of further characters, both morphological and molecular, a difficult task in a group characterized by reduction in morphology and size.

Giménez, L.¹ and Anger, K.²

¹ Sec. Oceanografía, Fac. de Ciencias, Iguá 4225, 11400 Montevideo, Uruguay ² Biologische Anstalt Helgoland Stiftung Alfred-Wegener-Institut für Polar- und Meeresforschung, 27498 Helgoland, Germany

Relationships between initial larval size, developmental pathways, and juvenile size and survival in Chasmagnathus granulata (Decapoda, Grapsidae)

Chasmagnathus granulata, an estuarine crab, shows two alternative developmental pathways, with 4 (short pathway, SP) or 5 zoeal stages (long pathway, LP). In laboratory experiments, we investigated (1) if the proportion of larvae following the LP depends on initial larval size (expressed as dry weight and carbon content at hatching); (2) the consequences of different pathways for subsequent megalopal development and postsettlement growth and survival. Larvae hatching from smaller eggs tended to follow the LP. As a consequence, metamorphosis in LP individuals occurred with an average delay of ca 7 days, implying a potentially reduced fitness due to competition with earlier settlers. However, LP individuals showed a significantly larger size in the megalopa and crab instars, and early LP juveniles survived for a longer time under starvation than SP crabs. Thus, the potentially disadvantageous developmental delay was partially compensated by larger body size and a decreased nutritional vulnerability after metamorphosis.

Glenner, H.¹ and Spears, T.²

¹Department of Evolutionary Biology, Zoological Institute, University of Copenhagen, 15 Universitetsparken, DK-2100, Copenhagen, Denmark ²Department of Biological Science, Florida State University, Tallahassee, Florida, U.S.A 32306-1100

Phylogenetic analysis of Cirrripedia Rhizocephala based on molecular data

Rhizocephala is a group of parasitic crustaceans that exclusively parasitize other crustaceans. Their adult morphology is extremely reduced, and it would be difficult, based on the few morphological characters alone, to place them within Crustacea. However, their unique larvae reveal a whole suite of characters that undoubtedly place them within the Cirripedia. Recent larval-based morphological and molecular data suggest a sistergroup relationship between Rhizocephala and Thoracica, but internal relationships within Rhizocephala remain vague, and molecular data have never been applied. We present a rhizocephalan phylogeny based on 18S rDNA sequence data. Twenty rhizocephalan species representing six families were sequenced and sequences for thoracicans, acrothoracicans and ascothoracicans (as outgroups) were downloaded form GenBank. Preliminary results suggest: (1) monophyly for the Cirripedia, Thoracica, and rhizocephalan suborder Akentrogonida; (2) no support for a monophyletic Rhizocephala; (3) Akentrogonida form the sister-group to a (Kentrogonida + Thoracica) clade.

González-Gurriarán, E., Bernárdez, C., Freire, J. and Fernández, L.

Dpto. Bioloxía Animal, Campus da Zapateira, s/n. E- 15071 A Coruña. Spain

Migratory patterns of the spider crab, Maja squinado, in North and South Galicia (NW Spain): preliminary results

In early September 2000, 40 female and 30 male spider crabs were tagged using data storage tags (Vemco Minilog-TDX and Star Oddi DST-200), in two locations at the South and North of Galicia (Ría de Arousa and Ría de A Coruña, respectively). In January 2001, recapture rates reached 78.9% in the South and 39.4% in the North. Average permanence in the sea was 68.6 days. Movement was characterized by a first period (around 1 month) of small-scale movements at a constant depth (10-20 m). After this, the crabs perform a migration that lasts 1 to 10 days (average: 5 days), in which they reach their maximum depth, 68 m in the North (ranging from 33 to 170 m) and 39 in the South (18 to 65 m). Average migration start date was 29/09/2001, and it finished by 05/10/2001, with a 1 day delay of the South location. Migration occurred one month earlier than in previous years. The analysis of meteorological and oceanographic data will give light to this point, since autumn 2000 was unusually rainy (the highest in this century) and several storms affected the coast.

Goshima, S., Minouchi, S. and Yoshino, K.

Graduate School of Fisheries Sciences, Hokkaido University, Hakodate, Japan

Size assortative mating in the hermit crab Pagurus filholi.

The hermit crab Pagurus filholi exhibits precopulatory guarding behavior in which males drag the shells occupied by ripe females. Our previous study suggested that the male hermit crabs might adopt a mating strategy of pairing with the first ripe female they encounter. If so, we could expect a random pairing by size. However we observed size assortative pairing in the field: larger males tended to mate with larger females. We conducted several field observations and laboratory experiments to examine the following possible causes for the size assortative mating; 1) mate choice, 2) mate availability, and 3) constraints. Males did not prefer larger females in size, they often took over guarded females from smaller males, and smaller males could not drag larger females. These results suggest that the loading constraint hypothesis may explain the observed size assortative mating in the hermit crab.

Gouws, G. and Stewart, B.A.

Department of Zoology, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa

Genetic differentiation in the freshwater isopod Mesamphisopus capensis (Phreatoicidea: Amphisopodidae) in the Western Cape, South Africa: phylogeographic insights

Mesamphisopus capensis is the most widespread of the four described phreatoicidean species in South Africa. Genetic differentiation at 12 allozyme loci was examined amongst ten populations across the known distribution of the species. Hierarchical F-statistics revealed significant genetic sub-structuring both between and within examined regions. Marked genetic divergence was observed between two population groups, collected either side of the dry, low-lying Cape Flats. This pattern of differentiation is compared to patterns seen in other crustacean and animal groups, and is discussed in the light of paleoclimatic change. In addition to extensive morphological differentiation among populations, individual populations were often distinguished from geographically proximate populations by fixed allelic differences or strong heterogeneity, while FST-values typical of highly structured distributions were observed across most loci in both regions (Cape Peninsula and Hottentots Holland Mountains). The implication of such sub-structuring for the conservation of the species is explored, and management units are identified.

Gouws, G., Daniels, S.R. and Stewart, B.A.

Department of Zoology, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa

Allozyme electrophoresis demonstrates the presence of a species boundary in freshwater crabs (Decapoda: Potamonautidae)

Potamonautes granularis, P. perlatus and P. sidneyi are morphologically similar freshwater crab species occurring in South African rivers. Clinal morphological differentiation is seen between the typical 'P. sidneyi' and 'P. perlatus' morphotypes, and their specific status has been questioned. Potamonautes granularis, a cryptic species, was recently delineated from P. perlatus. This study examines species boundaries between these species, using allozyme electrophoresis. Twenty-five populations, collected along a 2 300 km transect, were analyzed for variation at 11 loci. Mean genetic identities obtained in comparisons of populations of different species were typical of interspecific comparisons within invertebrates. One fixed allele difference (ME-locus) distinguished P. granularis and P. sidneyi. Hybrid zones were observed between P. granularis and P. perlatus, and P. perlatus and P. sidneyi. These species pairs are distinguished by heterogeneity at the PGM- and GPI-loci, and ME-locus, respectively. Genetic data supports the recognition of three distinct species, despite extensive morphological variation.

Grabowski, M.¹, Grater, W.D.² and Stuck, K.C.²

¹Department of Invertebrate Zoology & Hydrobiology, University of Lodz, Lodz, POLAND ² Gulf Coast Research Laboratory, University of Southern Mississippi, Ocean Springs, USA

Ice age and phylogeography of penaeid shrimps in the region of Gulf of Mexico and Western Atlantic. Case study: pink shrimp, Farfantepenaeus duorarum (Burkenroad, 1939)

A general phylogeographic pattern observed in a variety of marine taxa inhabiting the southeastern region of the United States implies a deep phylogenetic division between Atlantic and Gulf of Mexico populations. It is attributed to almost complete isolation of the two basins during Pleistocene. That pattern is often generalised for all marine taxa of the area. However, the same large scale factor (e.g. glacial) can affect individually species of different environmental requirements. In the present study, phylogeography of the pink shrimp, Farfantepenaeus duorarum, has been examined using mtDNA marker. Analysis of the molecular variance (AMOVA) performed on three geographic scales (between basins, among populations within the basins and within populations) revealed that more than 95% of the genetic variance was explained by the differences within local populations. In fact, neither branching order within the constructed parsimonious trees, nor the topologies of trees based on the genetic distance matrix, revealed the presence of genetically discrete populations of this species throughout studied geographic range. Analyses of haplotype distribution and frequencies indicated recent colonization event. Based on the above, a model of post-pleistocene migration of the species from the glacial refugium to its present range is proposed and discussed in the context of penaeid shrimps phylogeny, habitat preferences and distribution in Western Atlantic.

Gribble, N. and Hay, T.

Queensland Department of Primary Industry, Brisbane, Qld, Australia

Estimation of mudcrab stock in northern Australia

Stock size is a key parameter used in predicting a fisheries production potential and sustainability, yet no stock estimates are available for Australian mud crab fisheries. To address this lack, a five-year research plan for the Northern Australian mud crab fishery (WA, NT, Qld) was developed at the "Northern Australia Mud Crab Research Priority" workshop, Darwin, May 1999. Two priority areas identified and are to be addressed in the current study; 1) Mapping of critical mud crab habitat. Habitat mapping techniques include interpretation of satellite imagery and detailed analyses of high resolution SPOT imagery, aerial photography and subsequent field team ground truthing and validation. Research will first be undertaken in the first year to determine the curent holdings of imagery and identify gaps in coverage across northern Austrailia. 2) Development of techniques for mud crab abundance estimation. Once habitat mapping is complete and sampling protocol is defined, the subsequent two years of the project will focus on the estimation of mud crab abundance in tidal mangrove creek habitat, mudflat/ foreshore areas, and upper reaches/ saltmarsh areas. The mud crab sampling protocol is based on techniques combining mark re-capture and depletion studies. Pilot studies have been undertaken in Qld and NT to test for robustness and appropriateness in each habitat area. The aim of the project is to provide the fishing industry and managers with an: Estimate of the size of the northern Australian (NT, QLD, WA) mud crab stocks for sustainable development of the fishery. Identification and quantification of critical mud crab habitat (NT, QLD, WA). And advice on future monitoring methods for northern Australian mud crab stocks.

Gross, M.Y., Morritt, D., Thorndyke, M.C. and Crane, M.

School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey, TW20 0EX, U.K.

Malformations in embryos of the amphipod Gammarus pulex (L.) exposed to chemicals released from sewage treatment works

The oestrogenic or anti-oestrogenic properties of an increasing number of widely used industrial and agricultural chemicals have been found to interfere with the reproduction and development of many organisms. While the effects on vertebrate species are well documented, far less is known about their role in and effects on invertebrates. The aim of this study was to determine whether environmental oestrogens and anti-oestrogens, known to be present in the effluent from sewage treatment works (STWs), are capable of adversely affecting the embryonic development of the freshwater amphipod Gammarus pulex. Gravid females were sampled below two STWs known to release endocrine disrupting compounds along the River Lea, UK and at a reference site in the River Mimram, a tributary of the Lea. Fecundity and frequency of malformed, undifferentiated, enlarged and dead embryos per female were determined. Results obtained from field transplantation studies and laboratory exposures to nonylphenol and effluent are presented.

Guerra-García, J.M. and García-Gómez, J.C.

Laboratorio de Biología Marina, Departamento de Fisiología y Biología Animal, Facultad de Biología, Universidad de Sevilla, Apdo. 1095, E-41080, Sevilla, Spain

The grain size influence on the crustacean recolonization of soft-bottom benthos: a field experiment

A field experiment was carried out at Ceuta (North Africa) to test the effect of particle size on the crustacean recolonization of soft bottoms communities. Defaunated fine and gross sand with similar values of organic matter was used in experimental trays placed at the subtidal levels (3 meters deep). A total of 96 plastic trays (25 x 20 x 7 cm³) were used. Six sampling were carried out 3, 7, 15, 30, 60 and 90 days after the trays were placed at the bottom. The recolonization occurred extremely fast existing already 8 species after 3 days of the recolonization process, indicating the importance of the beadload transport of adults, otherwise neccesary for most of the species, which present direct development. The maximum value, 23 species registered after 3 months, was higher than the control value in the zone (about 10 species) as the trays are acting as patches at the bottom. Although the majority of the species living in the control area could indistinctly colonize both sediment types, the values of species richness, diversity and evenness were higher in gross sand than in fine sand trays. The gammarids Aora spinicornis, Cheirocratus sundevallei and Siphonoecetes dellavellei and the tanaid Apseudes latreille significantly preferred the gross sand while the gammarid Dexamine spinosa and the caprellid Pariambus typicus were more abundant in fine sand trays.

Guerra-García, J.M., Corzo, J., Vega, M. and García-Gómez, J.C.

Laboratorio de Biología Marina, Departamento de Fisiología y Biología Animal, Facultad de Biología, Universidad de Sevilla, Apdo. 1095, E-41080, Sevilla, Spain

Structure of the peracaridean community from an estuarine zone of Southwest Spain

Peracarid crustaceans are very important as secondary and thirly producers in marine benthic communities. We studied along an annual cycle the peracarids inhabiting the infralittoral community of the estuarine zone of El Portil, Southwest Spain. Quantitative samples of substrates (the seaweeds Sargassum vulgare, Cystoseira usneoides, Dyctiopteris membranacea and the briozoan Bugula neritina) were collected monthly from January 2000 to February 2001 by means of square metal frame (30 x 30 cm²). Temperature and salinity were also measured along the year. Twenty species of peracarids were identified, 17 amphipods, 2 tanaids and 1 isopod. The gammarids Aora spinicornis, Corophium acutum, Dexamine spinosa, Elasmopus affinis and Ericthonius punctatus, the caprellid Phtisica marina, and the isopod Dynamene torelliae were the dominant species, present during all the year. While the biomass of Sargassum vulgare and Cystoseira usneoides was increasing from January to July, disappearing in August due to the high temperature and salinity, the biomass of Dictyopteris membranacea was favoured by these summer environmental conditions increasing from July to December. The majority of the peracaridean species living in the studied estuarine zone were present all over the year and turned to be very unspecific by the substrate. This strategy let them survive along the whole annual cycle since they are able to "move to another house" depending on the different substrate availability according to the seasonality and environmetal conditions.

Guerra-García, J.M.¹, González-Vila, F.J.² and García-Gómez, J.C.¹

¹Laboratorio de Biología Marina, Departamento de Fisiología y Biología Animal, Facultad de Biología, Universidad de Sevilla, Apdo. 1095, E-41080, Sevilla, Spain ²Instituto de Recursos Naturales y Agrobiología de Sevilla, Consejo Superior de Investigaciones Científicas, Apdo. 1052, E-41080, Sevilla, Spain

Crustaceans and pollution in harbours: the importance of oxygen in the water column. Case study: the harbour of Ceuta

The harbour of Ceuta, North Africa, presents and unusual structure being located between two bays connected by a channel, which increases the water movement and renovation along the harbour, resulting to maintaining moderate oxygen levels in the interface water-sediment. Nevertheless, high concentration of pollutants were measured in sediments from this harbour. The intensity of ship traffic together with the waste discharges of non-depurated effluents have conducted to increase the levels of organic matter, hydrocarbons in particular, and heavy metals (specially from the antifouling paintings). Under these unusual conditions (high level of pollution and saturation of oxygen in the interface water-sediment) we studied the response of macrobenthic crustacean communities. Twenty one soft bottom stations were selected along the harbour area (internal versus external stations). According to the univariate analysis, the crustacean species richness, diversity and evenness were not significantly different between external and internal stations in spite of the high levels of pollutants in the latter. Furthermore, the environmental models log-normal and ABC (abundance biomass comparison) curves did not reflect stress levels in the communities. Nevertheless, the multivariate analysis based on the species abundance and environmental variables were able to differentiate between the stations. In this case, the positive effect of oxygen probably contribute to maintaining non-stressed benthic communities inside the harbour although the species living at external and internal stations are different. Oxygen levels seems to determine the "quantity" of species whereas the pollutants determine the "quality" of them.

Gusmão, L.F.M. de and Montú, M.A.

FURG, Departamento de Oceanografia, Laboratório de Zooplâncton, Av. itália, Km. 8, s/n, Rio Grande, Bairro Carreiros, C.P. 474, Brazil

Some Biological Aspects of two species of the genus Metamysidopsis (Crustacea : Mysidacea) of the southern coast of Brazil

Metamysidopsis elongata atlantica (Holmes, ) and Metamysidopsis munda (Zimmer, 1918) are two common species of Mysidacea found in the southern coastal zone of Brazil, especially in sandy beaches and the Patos Lagoon estuary in the Rio Grande do Sul State. In spite of their wide distribution and abundance, little is known about their biology. Some aspects of seasonality, reproduction, development, growth and biomass of specimens collected in the field and reared in laboratory were studied. The females of these two species attained at maturity a similar size range (5,12 - 7,12mm) but M. munda produced a higher number of larvae per brood. In general, the mature females average size of the two species were larger than the adult immature females and males. Field and laboratory results were compared. Seasonal variation of size, egg production and sexual biomass were observed suggesting different reproductive strategies.

Han Xifu and Wang Rong

Marine Ecological Center, Institute Of Oceanology, Chinese Academy Of Science, 7#Nanhai Road, Qingdao, Shandong Province, P. R. China, 266071

Respiratory physiology in summer diapause embryos of the neustonic copepod, Calanus sinicus in The East China Sea

The respiratory physiology of summer diapause stage of the neustonic copepods Calanus sinicus, maintained in 25 C and light 12h light:12h dark condition was characterized by a bell-shaped curve, with low O₂ uptake levels at the beginning of dormancy. This was followed by a steady rise in O₂ consumption with temperature decreased from 25 C to 15 C with maximum levels 0.0042 µl O₂ at 20 C. When the embryos were subject to 20ºC, the respiration activity was almost 3 times than at 25 C, even though both respiratory curves were similar. The results of temperature shock experiments, in which eggs were in situ of Yangtze river bayou in C. sinicus differs considerably from were first kept at warmer temperature for several weeks, after which the temperature was fallen to 15 C for a number of weeks later, the eggs was observed hatching occurred. By contrast, as long as egg kept in 20-25 C all the time, no hatching was observed, suggesting that low environmental temperature are essential prerequisite for hatching of this eggs. This type of diapause in C. sinicus differs considerably from the other smaller copepods, Paracalanus parvus. In this case, there is a U-shaped respiratory curve with greatest O₂ consumption to the onset or upon breaking of diapause. Differences in the two type of diapause seem to involve not only differences in O₂ consumption levels but also in the sequence of metabolic changes with time and the metabolic requirements during summer dormancy.

Haney, T.A.

Department of Organismic Biology, Ecology, and Evolution, University of California Los Angeles, Los Angeles, USA and Research and Collections, Natural History Museum of Los Angeles County, Los Angeles, USA

Hitchhiking amphipods: morphological adaptations of the whale-lice

The amphipod family Cyamidae comprises 28 species commonly known as whale-lice. Cyamid amphipods live in an obligate symbiotic association with whales, dolphins, and porpoises. A brief review of the systematics of the Cyamidae is provided, after which a phylogenetic tree is used as a template upon which to trace the evolution of morphological characters. Cyamid features presumed to have evolved as a result of life on whales are illustrated and discussed. Other aspects of the extraordinary association between these Crustacea and their mammalian hosts are also discussed.

Haney, T.A. ¹² and Martin, J.W.²

¹Department of Organismic Biology, Ecology, and Evolution, University of California Los Angeles, Los Angeles, USA ²Research and Collections, Natural History Museum of Los Angeles County, Los Angeles, USA

Who is "pugettensis"?: a closer look at Nebalia on the West Coast of the United States

Until 1996, populations of leptostracan Crustacea along the western coast of North America were thought to represent a single species, Nebalia pugettensis Clark, 1932. Because the description of N. pugettensis was inadequate and type specimens were never deposited, N. pugettensis was later declared to be invalid. To revisit the taxonomic status of N. pugettensis and other Leptostraca of the West Coast, relationships among multiple populations of Nebalia are inferred from morphological and molecular (cytochrome oxidase gene) evidence. The material under study represents collections from Baja California Sur to Puget Sound, Washington, the latter of which represents the type locality of N. pugettensis. The results confirm the presence of multiple leptostracan species from shallow waters of the western coast of North America.

Haney, T.A.¹² and Martin, J.W.²

¹Department of Organismic Biology, Ecology, and Evolution, University of California Los Angeles, Los Angeles, USA ²Research and Collections, Natural History Museum of Los Angeles County, Los Angeles, USA

A new leptostracan genus from the British Virgin Islands.

With recent efforts targeted at the study of nebaliacean specimens from field and museum collections, it is becoming clear that the order Leptostraca might be incredibly diverse. Indeed, six of the ten known genera have been described in the last 17 years. One of these, a new genus and species of leptostracan, is described from material discovered in shallow waters of Guana Island, British Virgin Islands. The specimens were collected from light traps and colonies of the green alga Halimeda. The new genus is described and illustrated. It differs from other leptostracans in the morphology of the antennule and the eighth thoracopod. While its eyes, like those of Nebalia, are non-tuberculate, it shares the rostral spine, dentate margin of antennular article four, and serrate pleopodal protopods of Levinebalia and Paranebalia. However, the new genus lacks features characteristic of Levinebalia, Nebalia and Paranebalia.

Hansen, B.

School of Zoology, University of Tasmania, Hobart, Australia

Allozyme geographic variation in populations of freshwater crayfish: a case of incipient speciation?

The Tasmanian endemic freshwater crayfish genus Parastacoides is presently under review. This paper reports on allozyme variation in populations of one of the proposed species. Specimens of this species were collected from three discrete geographic localities based on major drainages, and were analysed using 15 polymorphic allozyme loci and the 16S region of the mitochondrial DNA. The study indicates allozyme differences between populations suggesting differentiation along geographic lines (major drainages). An examination of percent fixed differences of loci between sample sets reveals values ranging between 6% and 44%. Due to a suspected secondary structure, sequencing of the 16S segment was interfered with by a compression of the first 100 bp of all individuals, which may indicate a shared genetic history. A large proportion of the distribution of this new species has been heavily glaciated on at least four occasions during the Pleistocene, isolating populations in coastal refugia. It may be that these populations are on the brink of speciation, due to repeated episodes of isolation.

Held, C. and Wägele, J.-W.

Lehrstuhl für Spezielle Zoologie, Ruhr-University of Bochum, Bochum, Germany

How common is a circumpolar distribution pattern in the high Antarctic benthos really?

The Antarctic marine ecosystem is roughly characterized by a number of relatively isolated subantarctic islands and a continuous belt of benthic habitats around the Antarctic continent itself. For many taxa of the Antarctic benthos a circumpolar distribution is regarded as the rule, surrounded by species confined to the subantarctic archipelagos. This view, which is in agreement with the relative isolation of Antarctic habitats today, is challenged by molecular data from Antarctic benthic crustaceans. Seven species of crustaceans have been studied over a geographic range and the variability of mitochondrial molecular markers was determined. Preliminary results indicate that (1) the populations of some, but not all, species are genetically highly structured, (2) cryptic speciation may be more common than previously recognized, (3) the distribution of genotypes is horizontally and also vertically stratified, (4) the inferred amount of geneflow may correlate with species‘ dispersal abilities. The implications of these findings on hypotheses concerning the historical biogeography and colonization of the Southern Ocean will be discussed.

Heras, Horacio

Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), CONICET-Universidad Nacional de La Plata, 60 y 120 (1900) La Plata, Argentina

Lipid dynamics during Macrobrachium borellii embryogenesis

Yolk stored in crustacean oviposited eggs serve as the single source of nutrition until larvae starts feeding, playing an essential role in embryogenesis and larval survival. The major nutrients in M. borellii vitellus are lipids, mainly triacylglycerols (TAG) and phospholipids (PL), followed by apolipovitellin. Embryos take up TAG and PL in early embryogenesis and oxidize them in the middle and at the end of development. This is reflected by the lipid composition, yolk mass and enzymatic activity changes. Mitochondrial fatty acid (FA) Beta-oxidation, cytosolic TAG lipase and microsomal palmitoyl CoA ligase becomes very active especially during organogenesis. FA composition change and PUFA becomes the major PL FA after organogenesis. Phospholipid synthesis is very efficient all along development, reflecting membrane biosynthesis, but surprisingly TAG and diacylglycerols are also actively synthesized during organogenesis. Therefore both anabolic and catabolic processes are very active, remodeling lipids and oxidizing FA at different rates as the embryo develops.

Hernández, J.E., Palazón-Fernández, J.L. and Hernández, G.

Escuela de Ciencias Aplicadas del Mar, Universidad de Oriente, Isla Margarita, Venezuela

The effects of salinity and temperature on the larval development of Stenorhynchus seticornis (Herbst, 1788) (Brachyura: Majidae) reared in the laboratory

Larvae of S. seticornis were reared in the laboratory in a factorial experiment employing three temperatures (22, 25, and 28 C) and three salinities (30, 35, and 40 ppt). Larvae were subdivided in groups of 10 and reared in plastic bowls containing filtered and UV-irradiated sea water at the different S-T combinations. Larvae were transferred daily to clean bowls and fed with newly hatched Artemia nauplii. Survival and molting were recorded. Salinity affected percent survival of the two zoeal stages, but not that of the megalopa. Survival in the second zoeal stage, and the megalopa was affected by temperature. Duration of all stages was inversely related to temperature. Salinity affected the duration of the first zoeal stage only. No megalopa molted to the first crab under 28 C, 35 ppt. Time required for development to the crab stage was 26.9, 21.0, and 19.7 days at 22, 25 and 28 C, respectively.

Hiwatari, T.¹, Maki, H.¹, Izawa, S.² and Kohata, K.¹

¹National Institute for Environmental Studies, Japan ²Department of Biology, Faculty of Science, Ibaraki University, Japan

Acute toxicity of water-soluble compounds from heavy fuel oil by natural sunlight to Hyale barbicornis (Amphipoda)

Acute toxicity of water-soluble compounds derived from a heavy fuel oil by sunlight irradiation to Hyale barbicornis (amphipod) was studied. Two glass bottles were filled with 10 l of seawater and 10 g of heavy fuel oil; one was exposed to natural sunlight (EB; exposed bottle), and the other was entirely shaded by aluminum foil (SB; shaded bottle) during an experimental period. In the toxicity test of EB, 96-h mortality of amphipod juveniles after day 7, 15, 21 and 28 were 50, 80, 100 and 100%, respectively. On the contrary, the mortality of the SB sample was approximately 10% throughout the test. An absorption spectrum of water-soluble fraction of the EB showed a peak at 213 nm. The absorbance increased linearly and attained 2cm^–1 after day 28. The concentration of dissolved organic carbon (DOC) also increased linearly and attained 30 mgl^–1. On the other hand, the absorbance and DOC of the SB sample remained in a low level during the study period. Water-soluble compounds in EB were composed of an aromatic aldehyde and aromatic cyclic ketones. Consequently, the toxicity of the water-soluble fraction to amphipod was attributed to that of oxidized compounds produced from a heavyfuel oil by sunlight irradiation.

Ho, J.S.

Department of Biological Sciences, California State University, Long Beach, CA, USA

Invasive parasitic copepods: Caligus lalandei Barnard, 1948 (Caligidae, Siphonostomatoida): a recent invader of the waters of Japan

Several species of parasitic copepods are invasive and colonized various species of fish hosts in many parts of the world. Among them are species of Lernaea and Lamproglena of the Lernaeidae (Cyclopoida), Neoergasilus and Paraergasilus of the Ergasilidae (Poecilostomatoida), and Caligus of the Caligidae (Siphonostomatoida). Most of these exotic invaders are freshwater species and spread by anthropogenic translocation of fish stocks for aquaculture. Caligus lalandei Barnard is a marine copepod parasitic on amberjacks (Seriola spp.). It was known only from South Africa, Mexico, Chile, and New Zealand. However, in 1989 it was discovered on "mojako" (juvenile amberjacks gathered for culture) of S. quinqueradiata caught off Kagoshima, Japan and in 1998 it appeared on S. lanlandi caught in a set net installed off Kangreung, Korea in the Sea of Japan. In 1999, C. lalandei was found parasitic on S. lalandi cultured in a cage-net operated in Oita, Japan. The parasite seems to be well established in the waters of Japan. The possible origin of the occurrence of C. lalandei in this new habitat is discussed.

Hoang, Tung¹, Lee, S.Y.¹, Keenan, Clive P.² and Marsden, Gay E.

¹School of Environmental & Applied Sciences, Griffith University, PMB 50 GCMC, Qld 9726, Australia ²Bribie Island Aquaculture Research Centre, QDPI, PO Box 2066, Qld 4507, Australia

Effects of overwintering conditions on growth, maturity and spawning performance of Penaeus merguiensis.

Because of the unreliable supply of quality broodstock of Penaeus monodon, the culture of species like P. merguiensis, which can mature and spawn naturally in captivity becomes more and more important. Culturing or holding P. merguiensis broodstock in subtropical areas like southeast Queensland, however, requires overwintering facilities during winter. This paper reports growth, sexual maturity and spawning performance of pond-reared P. merguiensis overwintered in three different types of facility: covered pond, outdoor and indoor tanks. Results showed that growth, sexual maturity and spawning performance were strongly influenced by water temperature and the availability of natural foods. Males matured at younger ages and smaller sizes than females. Size appeared to be the primary factor determining both the onset of sexual maturity and spawning performance of prawns. Prawn started mating at 6 months old; reached full ovarian maturation and started spawning from 8.5 months old, producing relatively high fecundity and viable larvae. The results of this study also suggest a great potential for using pond-reared broodstock P. merguiensis for hatchery production and for domestication/breeding program.

Hoang, Tung¹, Lee, S. Y.¹, Keenan, Clive P.² and Marsden, Gay E.

¹School of Environmental & Applied Sciences, Griffith University, Queensland, Australia ²Bribie Island Aquaculture Research Centre, QDPI, Queensland, Australia

Spawning behaviour of the banana prawn, Penaeus merguiensis de Man

Spawning behaviour of Penaeus merguiensis in laboratory conditions were fully described and, for the first time, presented by video. Spawning usually occurred between 19:30 and 22:30. The spawning process can be divided into four consecutive phases namely: (i) dormant; (ii) pre-spawning; (iii) spawning; and (iv) post-spawning by distinct behaviour of the spawners and different duration. During the dormant phase, the spawners were quiescent and were not feeding. Movement of the spawners, however, became active during the pre-spawning phase. Both prawn behaviour and ovary appearance changed progressively as the pre-spawning progressed. Depending on the individual, spawning was usually completed within 3-5 minutes. Eggs were actively dispersed into the water column by the spawner's pleopods. Active movement of the spawners were re-exhibited in the post-spawning phase, presumably to facilitate fertilization. The spawning behaviour of P. merguiensis, available in video through this study, may be a useful material for teaching crustacean biology.

Hobbs, Horton H., III.

Department of Biology, Wittenberg University, P. O. Box 720, Springfield, Ohio 45501,USA

A synopsis of the stygobitic crayfishes of the karst regions of the United States (Decapoda: Cambaridae)

Within the contiguous United States, thirty-four species and subspecies of stygobitic (cave-adapted, obligate groundwater species) are assigned to four crayfish genera. These crustaceans occur primarily in the karst areas where caves are developed in limestone and other soluble rocks of the Appalachians, Florida Lime Sink, Interior Lowlands, and the Ozarks. Eleven species of Cambarus (4 subgenera) are known from the Appalachians, the Interior Lowlands, and the Ozarks; eight species and subspecies of Orconectes are recognized from caves of the Interior Lowlands and a single cave in south-central Missouri; 14 species and subspecies of Procambarus are found in ground waters in Alabama and Florida; and the monotypic Troglocambarus has been found in caves, sinks, and spring caves in north-central Florida. Of particular interest is the puzzling biogeographical question of why a recently discovered species of Orconectes is the only cave-adapted member of the genus known west of the Mississippi River and sandwiched between cave-adapted Cambarus spp.

Holmes, Janet M.¹, Magnay, Julia L.¹, Neil, Douglas M.² and El Haj, Alicia J.¹

¹Keele University, Keele, UK. ²University of Glasgow, Scotland, UK

Effects of elevated rearing temperature on myosin heavy chain gene expression and muscle function in Homarus gammarus.

Temperature affects the functional characteristics of muscle through the expression of different myosin heavy chain isoforms. The nucleotide sequences of surface loops 1 (enzyme-binding site) and 2 (actin-binding site) determine the thermal stability and activity of myofibrillar ATPases, and ultimately the speed of contraction. Rearing temperature of ranched lobsters is critical for successful aquaculture, but little is known about its effect on muscle function in young juveniles. This study investigates the effects of thermal acclimation on myosin gene expression in the European lobster, Homarus gammarus. Total RNA was extracted from the fast and slow muscles of the claw and abdomen of stage 11 larvae (acclimated from 6th stage) and juveniles acclimated for 6 months to 10, 15 and 20 C. Using RT-PCR, degenerate oligonucleotide primers identified temperature-dependent and developmental myosin isoforms, which varied in loop length and charge. Such thermal modulation of the muscle function through the expression of different myosin isoforms may influence the ability of juvenile lobsters to escape threatening situations when released.

Hong, S.Y.¹; Sankarankutty, C.² and Cunha, I.M.C. da²

¹Department of Marine Biology, Pukyong National University, 608-737 Pusan, Korea. ² Museu do Mar "Onofre Lopes", Universidade Federal do Rio Grande do Norte, Natal RN - 59014-100, Brazil

Description of laboratory reared first zoea of Hexapanopeus manningi Sankarankutty & Ferreira (Crustácea: Decapoda: Xanthidae)

Hexapanopeus manningi Sankarankutty & Ferreira, a xanthid crab known so far only from the type locality, is common in the estuaries of the State of Rio Grande do Norte, Brazil (Sankarankutty & Ferreira, 1999). It inhabits from the littoral to shallow sublittoral regions where the substratum is covered with stones and broken shells. The first zoeae of the species were obtained in the laboratory from berried females maintained in aquaria as well as from in vitro experiments (Sankarankutty et al. 1999). A detailed description of the larvae and a comparison of the morphological features with related species are presented here.

Hu, K.J. and Leung, P.C.

Department of Zoology, The University of Hong Kong, Pokfulam road, Hong Kong, SAR, China

Cloning and characterization of cathepsin-L genes of marine shrimp Metapenaeus ensis.

Two cathepsin-L cDNAs have been isolated from the hepatopancreas cDNA library of the marine shrimp Metapenaeus ensis. PCR amplification of the genomic DNA with isoform-specific primers verified the co-existence of the two cDNAs. Cathepsin-L2 may be derived from a deletion of cathepsin-L1 by the slipped strand mispairing after gene duplication. Northern analysis showed that cathepsin-L is strongly expressed in hepatopancreas. RT-PCR analysis showed that cathepsin-L is also expressed in intestine, stomach, ovary and muscle. Cathepsin-L1 was expressed in bacteria with pRSET(B) and was purified with a metal affinity column. The polyclonal antibody against the recombinant cathepsin-L1 was raised. Western analysis of the extracted shrimp proteins suggests that cathepsin L exists in hepatopancreas, intestine and stomach. PCR cloning of genomic DNA with cathepsin-L specific primers revealed that there is no intron in the cathepsin-L gene, different from the cathepsin-L gene of another marine shrimp Penaeus vannamei, which possesses five introns.

Huys, R.

Department of Zoology, The Natural History Museum, London SW7 5BD, UK

Copepod evolution: ten years on

Existing classifications and phylogenetic hypotheses of the copepod orders were traditionally based on inaccurate, incomplete or wrongly interpreted data. Huys & Boxshall (1991) recognized that establishing a reliable classification of the Copepoda, based on a robust phylogenetic framework, required a rigorous scheme for determining homologies between morphological character states and a complete re-examination of primitive representatives of all ten orders. They proposed a new hypothesis of phylogenetic ordinal relationships within the Copepoda which, though being widely adopted, has been criticized on methodological grounds (Ho, 1994). This presentation reviews the new relevant morphological data accumulated during the last decade and for the first time presents sequence data for the complete18S rRNA gene data from a selected range of taxa. The molecular data will be used to test whether (1) oligomerization is the predominant mode of character transformation in copepod evolution, involving fusion and loss of body somites and appendage segments, and loss of setation elements, (2) incongruence caused by character reversal is indeed as exceptional as previously asserted by Huys & Boxshall (1991), and (3) the three major parasitic orders (Cyclopoida, Poecilostomatoida, Siphonostomatoida) are natural units or para/polyphyletic assemblages.

Hwang, J.-S.¹, Tseng, L.-C.¹, Chen, Q.-C.², Shih, C.-T.³, Hung, J.-J.⁴ and Wong, C. K.⁵

¹Institute of Marine Biology, College of Fisheries Science, National Taiwan Ocean University, Keelung,, Taiwan, ROC ²South China Sea Institute of Oceanology, Academia Sinica, Guangzhou, China ³Taiwan Fisheries Research Institute, Keelung, Taiwan, ROC ⁴Institute of Marine Geology and Chemistry, National Sun Yat-Sen University, Kaohsiung, Taiwan, ROC ⁵Department of Biology, The Chinese University of Hong Kong, Shatin, Hong Kong

Taxonomic composition and grazing rate in the major group of copepods in the northern South China Sea

Zooplankton composition and grazing rate in the major group of copepods was studied in the northern South China Sea. Zooplankton were sampled along the transect line from Taiwan to the northern South China Sea during the cruise 563 of Ocean Research Vessel III from September 27 to October 2, 1999. The sampling stations covered the most southern site of South East Asia Time-series Station (SEATS). Zooplankton were collected within upper 5 meters of each station by horizontal tows using 100onm mesh nets and by 100 meter oblique tows using 333m m mesh nets. Fifty-one species of copepods were identified. Acartia negligens and Corycella gibbulus were found over the entire study area. Acrocalanus gracils, Centropages arcuicornis, Corycaeus agilis, Nannocalanus minor, and Temora discaudata were found in most sampling stations (n=5) from Taiwan to South East Asia Time-series Station (SEATS). Euchaeta rimana, Labidocera acuta, Labidocera minuta, Temora turbinata, and Corycaeus andrewsi were rarely observed species in the study sites. They occurred only once along the transect line from Taiwan to SEATS. The most common and dominant genera were Paracalanus spp., Calocalanus spp. and Othina along the transect line. Gut pigment content of 33 species was measured with the gut fluorescence method. The variability of the gut pigment contents for a single species among the sampling stations was high. Ingestion rates were calculated from gut pigment data. The highest values were observed in Scolecithrix danae, Undinula vulgaris, Cosmocalanus darwini, and Pleuromamma gracilis.

Høeg, J.T. and Lagersson, N.C.

Dept. of Zoomorphology, Zool. Inst., Univ. Copenhagen, Universitetsparken 15, DK-2100, Copenhagen, Denmark

"The complete cypris": apomorphies characterizing the settlement stage of the Cirripedia

The cypris is the terminal larval instar, which initiates the sessile mode of life found in all three orders of cirripedes. To accomplish this critical event in the life cycle, the cypris has a unique set of morphological specializations. This presentation emphasizes the uniqueness of the true, cirripede cypris compared to the homologous, but more plesiomorphic larvae found in the Ascothoracida and the Facetotecta. The numerous apomorphies characterizing the cirripede cypris include details of the head-shield, the complex segmentation of the antennules, the glandular apparatus, the sense organs, the thoracic appendages, and distinct differences between the fast action in muscles in the thorax used for swimming and the postural muscles in the antennules used in exploratory walking, and a hindbody with only a rudimentary abdomen. Together, these apomorphies correlate with the role of the cypris in substrate location and and attachment, and they support the monophyly of the Cirripedia despite the vastly different morphology and mode of life found in adults of the three suborders. CANCELLED

Høeg, J.T.¹ and Pasternak, Z.²

¹Dept. of Zoomorphology, Zool. Inst., Univ. Copenhagen, Universitetsparken 15, DK-2100 Copenhagen, Denmark ²Institute for Marine Conservation Research, Tel-Aviv University,Tel-Aviv, 69978 Israel

The ultrastructure of chemosensory aesthetascs in cypris larvae of parasitic barnacles (Cirripedia: Rhizocephala)

The Rhizocephala are a group of specialized Cirripedia that are parasites as adults. Since the adult cirripede cannot change its locale, the task of locating a suitable habitat falls on the last free-swimming larval instar, known as the cyprid. Rhizocephalan cyprids use a number of cues in order to help locate their settlement targets, most importantly chemical signals emanating from the host. The major chemosensory organs are lattice organs in the head shield and aesthetascs, which are large sac-like organs attached to the tip of the antennule. The lattice organs have been recently studied using SEM and TEM techniques, but the aesthetascs have so far been neglected. We describe the ultrastructure of aesthetascs in rhizocephalan cyprids using both SEM and TEM. Male and female cyprids differ in their choice of settlement substratum and this correlates with a distinct morphological difference in the armature of aesthetascs. These are sac-like setae enclosed by an extremely thin epicuticle. Sensory cells located in the antennule carry ciliary segments that branch profusely before entering the aesthetasc.

Høeg, J.T.¹, Waloszek, D.², Maas, A.² and Müller, K.J.³

¹Dept. Zoomorphology, Zool. Inst., Univ. Copenhagen, Universitetsparken 15, DK-2100, Copenhagen, Denmark ²Sect. Biosyst. Doc., Univ. Ulm, Helmholtzstrasse 20, D-89081 Ulm, Germany ³Inst. Palaeontology, University of Bonn, Nussallee 8, D-.53125 Bonn, Germany

Dala peilertae Müller, 1983, a possible derivative of the stem lineage of Maxillopoda (Entomostraca, Crustacea)

Origin and monophyly of the Maxillopoda have remained controversial since its erection in 1956 by Dahl, although there is an obvious autapomorphy in the body tagmosis with a 7-segmented leg-bearing thorax (not 6 as originally thought) and a 4-segmented abdomen. We study Dala peilertae from the Swedish Upper Cambrian (Orsten), a putative stem line maxillopod, on the basis of almost 100 specimens preserved in full 3D aspect. The material shows a remarkable preservation of details, but the head is known only from fragments, leaving uncertainty about the exact relationships of this fossil. The 7-segmented thorax with large limbs and the 4-segmented abdomen indicate affinities of Dala peilertae with the Maxillopoda, whereas its sister-group position to all other maxillopods is indicated by the paragnath channel continuing in a flat thoracic sternal surface and the full set of setiferous basipodal endites on post-maxillular limbs, functioning for swimming and feeding, as in Cephalocarida and Branchiopoda. One of the major evolutionary trends within the crown group of Maxillopoda is seen in the deviation from a thorax serving for feeding and locomotion to exclusively locomotion.

Jacobucci, G.B.¹ and Leite, F.P.P.²

¹Programa de Pós-Graduação em Ecologia, Universidade Estadual de Campinas, Campinas, SP, Brazil ²Departamento de Zoologia, Universidade Estadual de Campinas, Campinas, SP, Brazil

Influence of habitat complexity and depth in the distribution of a peracarid assemblage associated with the brown alga Sargassum cymosum C. Agardh

Diversity and density variation in peracarid fauna inhabiting the sublittoral brown alga Sargassum cymosum at Lazaro Beach, Ubatuba, São Paulo State, Southeastern Brazil was temporal and spatially evaluated in order to examine the role of habitat complexity and depth in structuring this assemblage. Four seasonal samples were obtained during one year period at three depth intervals. Gammaridean amphipods were numerically dominant and were represented by a greater number of species than caprellidean amphipods, isopods and tanaids. Diversity and equitability presented little variability between depth ranges and periods of the year. Some species showed significant density differences among depth ranges that could be related to particular tolerances to hydrodynamic conditions and sedimentation over the depth gradient sampled. Habitat complexity variation, represented by differences in phenological characters, epiphytic algae and hydrozoan cover in Sargassum fronds, partially explained peracarid density distinction between plants and seasonal fluctuations of these organisms.

Jarman, Simon Neil

CSIRO Marine Research, GPO Box 1538, TAS 7001, Australia

Molecular evidence for paraphyly in the Mysidacea

The Mysida and the Lophogastrida are two groups of peracarid Crustacea that have often been grouped together in the order Mysidacea. A molecular phylogeny based on nuclear large subunit ribosomal DNA (28S rDNA) from Mysida, Lophogastrida and several other malacostracan orders indicated that the Mysida and Lophogastrida are distantly related. In fact, these two orders appear to have diverged early in the eumalacostracan radiation. This indicates either that the Mysidacea is a polyphyletic group and that the morphological characters that had united the two orders resulted from convergent evolution; or that the Mysidacea is paraphyletic and the shared characters are symplesiomorphies. The 28S rDNA phylogeny indicates that there is an incomplete understanding of the course of evolution in the Peracarida and Eumalacostraca as well.

Jazdzewski, K. and Konopacka, A.

Department of Invertebrate Zoology & Hydrobiology, University of Lodz, Lodz, Poland

A zoogeographical overview of the amphipod crustaceans of Northern Europe and of the Baltic, Black, and Caspian Seas

A thorough survey of ample amphipod literature resulted in updated lists of species of this crustacean group for the freswaters of Nothern Europe and for three brackish, continental basins: the Baltic, Black, and Caspian Seas. The Caucasus, Danube river (incl.), Alps, Central Massif and Garonne River (incl.) were assumed to be the southern borderline of Northern Europe. In this area some 130 amphipod species belonging to 10 families were recorded; the families richest in species were Niphargidae (subterranean, 59 species) and Gammaridae (29 spp). In the very young postglacial Baltic Sea, a boreal branch of the Atlantic, some 65 species were noted in 27 families, the family richest in species was Gammaridae (8 spp.). The Black Sea and Caspian Sea are remnants of Miocene Sarmatian brackish basin, where many brackishwater endemics originated, especially among Crustacea (Cladocera, Mysidacea, Cumacea, Amphipoda). The amphipod fauna of these two seas is dominated by the so-called Ponto-Caspian elements, with a dominant family Pontogammaridae. The connection of the Black Sea with Mediterranean resulted in the mixture of Atlantic-Mediterranean elements with Ponto-Caspian ones, which make over 35% of amphipod fauna numbering over 120 species in 29 families. In the isolated Caspian Sea Ponto-Caspian elements constitute over 70% of the total amphipod fauna, where some 75 species in 9 families have been noted.

Jazdzewski, K., Konopacka, A. and Grabowski, M.

Department of Invertebrate Zoology and Hydrobiology, University of Lodz, Poland

Recent drastic changes in the gammarid fauna of the Vistula river deltaic system in Poland, caused by alien invaders

In the last decade alien gammarid species, Gammarus tigrinus, Dikerogammarus haemobaphes and Pontogammarus robustoides invaded the lower Vistula river and its deltaic, partly brackish region. The main freshwater flow of this largest Polish river directly enters the Baltic Sea, whereas the western, old Vistula bed (Dead Vistula) and eastern Vistula Lagoon are brackish basins with a salinity of 2-7 ppt and 2-5 ppt, respectively. G. tigrinus is an oligohaline North-American species introduced into Dutch and German brackish waters around 1960. The species successively extended its range eastwards, also via the freshwater network of canals in northern Germany, reaching recently the Polish Baltic offshore waters, including the Szczecin Lagoon, Dead Vistula and Vistula Lagoon. D. haemobaphes and P. robustoides are brackishwater / freshwater Ponto-Caspian species which have recently invaded central and western Europe upstream the Danube river, also using man-made canals connecting the systems of the Black Sea (Dnieper and Danube rivers) and Baltic Sea (Vistula river) and North Sea (Rhine river). P. robustoides could use also another invasion route, namely offshore Baltic waters entering Vistula's deltaic system from the Lithuanian Kuronian Lagoon, where it was introduced in the 1960s. At present native European and Atlantic-boreal gammarid species: Gammarus pulex and G. varsoviensis in freshwater and G. zaddachi and G. duebeni in brackish waters are replaced or at least outnumbered by D. haemobaphes and P.robustoides (Vistula river) and by G. tigrinus and P. robustoides) (brackish Dead Vistula and Vistula Lagoon).

Jeffries, W.B.¹ and Voris, H.K.²

¹Department of Biology, Dickinson College, Carlisle, PA, USA ²Division of Amphibians and Reptiles, Field Museum of Natural History, Chicago, IL, USA

Pedunculate barnacles and biotic substrates: The genus Octolasmis as a case study

The life cycles of symbiotic Octolasmis species and their hosts are integrated with the important result that cyprid attachment, metamorphosis, and growth to reproductive adults, fit within host intermolt time periods. Octolasmis cor and Octolasmis angulata cyprid larvae collect on mangrove crabs, Scylla serrata, just prior to host molt. During ecdysis they transfer to the branchial chambers of the newly molted crabs. The spatial distributions of both barnacle species on the crab gills are nonrandom, uneven, and do not reflect available surface area. The two species are distributed differently on the hypobranchial (inside) and hyperbranchial (outside) gill surfaces. O. cor and O. angulata attain greater average size in some locations over others. Distribution patterns vary with different densities. Areas with higher densities also are areas of higher average fecundity. Thus it is apparent that the selection of the attachment site by the cyprid larvae does impact adult fitness parameters.

Jeffries, W.B.¹, Voris, H.K.², Poovachiranon, S.³, Heil, L.C.⁴, Hewitt, A.B.⁵, and Thavaradhara, K.⁶

¹Department of Biology, Dickinson College, Carlisle, PA, USA ²Division of Amphibians and Reptiles, Field Museum of Natural History, Chicago, IL, USA ³Phuket Marine Biological Center, Phuket, Thailand ⁴Pediatrics Department, Strong Memorial Hospital, University of Rochester, N.Y. 14607, USA ⁵Hanover Manor, Carlisle, PA, USA. ⁶Biology Dept, University of North Carolina, Greensboro, N.C. 27408, USA

Life cycle stages of the pedunculate barnacle genus Octolasmis Gray, 1825

Adult Octolasmis spp. carefully removed from crustacean hosts were maintained in the laboratory on a diet of brine shrimp larvae for an indefinite period. Detached gravid Octolasmis cor were a dependable source of nauplius 1 larvae. Adult O. cor placed in close proximity copulated in the laboratory. O. cor n1 and n2 larvae were cultured in filtered and aged sea water recently seeded with actively growing green algae. Two- and eight-liter glass cylinders were the culture vessels and they were maintained outdoors in shaded concrete enclosures, partially immersed in flowing sea water.

Johnsson, R. and Rocha, C.E.F.

Departamento de Zoologia, Universidade de São Paulo, R. Matão, trav. 14, no. 321 CEP: 05508-900, São Paulo, Brasil

Notes on homology of siphonostomatoid antennules

The homologies among antennules of siphonostomatoid females and the hypothetical ancestral state have continuously been analyzed in the most plesiomorfic siphonostomatoid families with the aid of two markers, a seta similar to a spine, and an aesthetasc, respectively located on the ancestral segments XIV and XXI. The present study uses the ontogenetic development of an Asterocheridae species plus the number of segments and setae of the adult female species studied to provide important basement to the antennule homology. These tools, together with the markers, are used to establish homologies among species of 15 siphonostomatoid families that are commonly associated to invertebrates. The results demonstrate that the antennules with few segments are more likely to be resulted from fail in separation than from fusion. Besides that it is observed similar patterns among families that share common hosts and slight modifications within families that have different hosts.

Johnsson, R., Neves, E., Rocha, C.E.F. and da Silveira, F.L.

Departamento de Zoologia, Universidade de São Paulo, R. Matão, trav. 14, no. 321 CEP: 05508-900, São Paulo, Brasil

Histological evidences of copepod association

Histological procedure is an important tool for a wide field of scientific knowledge, and so, may contribute for taxonomical purposes. Association between copepods and marine invertebrates has far been subject of interest, once it is not completely clear how those organisms could survive inside body cavities of their hosts. Parasitism and comensalism could be expected to occur, but unfortunately data dealing with copepod ecological relationships are few. Members of the class Anthozoa such as sea anemones, octocorals, zoanthids and scleractinian corals are known to shelter many copepods. The orders Siphonostomatoida and Poecilostomatoida have been reported in close association with coral colonies. Histological analyses of the Brazilian Siderastrea stellata, an endemic reef-bulding coral species, provided first evidences of the presence of copepods inside the coelenteron of polyps. So far only the highly modified copepods were found in endo-associations. Therefore, the present report also demonstrated that non-modified cyclopiform-like copepods may take a role as endo-habitants of coral polyps.

Johnsson, R.¹, Rocha, C. E. F.¹ and Boyko, C. B.²

¹Departamento de Zoologia, Universidade de São Paulo, R. Matão, trav. 14, no. 321 CEP: 05508-900, São Paulo, Brasil ²Division of Invertebrate Zoology, American Museum of Natural History, New York, USA

A new species of Cryptopontius (Copepoda: Siphonostomatoida) from Easter Island

The distribution of the genus Cryptopontius, family Artotrogidae, is essentially world-wide, being found in the Mediterranean Sea, Atlantic and Indian Oceans, and also the eastern Pacific. However, the discovery of a new species collected from Easter Island is the first occurrence of the genus in the western Pacific. The twenty-two species in the genus can be divided into three groups according to the number of segments in their antennules. This new species possesses a 9-segmented antennule, the third exopodal segment of leg 4 armed with 9 elements, and the second endopodal segment of P1 with 2 setae. The main differences between this new species and others in the genus are located on both lobes of the maxillule, on leg 5, and on the third exopodal segment of leg 1.

Johnston, Danielle J.¹ and Ritar, Arthur²

¹School of Aquaculture, Tasmanian Aquaculture and Fisheries Institute, University of Tasmania, Locked Bag 1-370, Launceston, Tasmania, Australia 7250. (corresponding author) ²Marine Research Laboratories, Tasmanian Aquaculture and Fisheries Institute, University of Tasmania, GPO Box 252C-49, Hobart, Tasmania, Australia

Mouthpart and foregut ontogeny in phyllosoma larvae of the spiny lobster Jasus edwardsii (Decapoda; Palinuridae)

The mouthparts and foregut structure of 10 stages of spiny lobster (Jasus edwardsii) phyllosoma were described using scanning electron microscopy and resin histology to investigate developmental morphology and its implications for diet. Mouthpart and foregut structure indicate that J. edwardsii phyllosoma ingest soft fleshy foods such as gelatinous bodied zooplankton. Mouthpart morphology changes little during larval development, indicating that ingestive capabilities and external mastication are well developed from an early age. However, the density and complexity of setation and robustness of individual mouthparts increases with age, suggesting a greater capacity to ingest larger prey during development. The foregut consists of a single chamber with a number of well-developed grooves, ridges and setae, but lacking a gastric mill. The primary role of the foregut is mixing, sorting and filtering particles, pre-ground by the mouthparts. Phyllosoma have been divided into early (stage I-III), mid (IV-V) and late (VI-X) stages based on the level of development of the filter press and main brushes. Increasing robustness of setation and complexity of the foregut suggests that the texture of prey becomes more muscular (fibrous) with larval development. The results presented here suggest that early stage phyllosoma would benefit from a diet comprising soft gelatinous items, while late stage phyllosoma are better prepared to deal with larger, fleshy prey. The changes in structural characteristics with age should also serve as a guide in the development of formulated diets.

Jones, D.S.

Department of Aquatic Zoology, Western Australian Museum, Perth, Western Australia 6000

Preliminary observations on the behaviour of the narrow fronted fiddler crab, Uca elegans George & Jones, 1982 in tropical north-western Australia

Fiddler crabs have traditionally been divided into two species groups: the "primitive" narrow fronts and the "advanced" broad fronts Crane (1957, 1975). In their taxonomic revision of the Australian Uca species, George & Jones (1982) included Uca elegans in the Deltuca group on the basis of morphological characters utilised by Crane. In a recent morphometric study of the world Uca species, however, Rosenberg (2000) placed U. elegans in the Australuca. To clarify the taxonomic status of Uca elegans, the social behaviour of the species was investigated by studies in tropical north-western Australia. There have been no previous studies on the behaviour of U. elegans. This study is mainly descriptive and as such, many features of the mating system, etc., remain to be experimentally verified. The purpose is to present hypotheses which appear consistent with the observational data and which may serve as a starting point for further analyses.

Jones, D.S.

Department of Aquatic Zoology, Western Australian Museum, Perth, Western Australia 6000

Distribution and biogeographic affinities of the Australian barnacle fauna

Information on the distribution of barnacles has not been well documented, prior to the work of Jones (19 ). Two hundred and seventy two species of barnacles are now known to occur in Australian waters. This study discusses patterns of distribution of barnacles in the tropical, subtropical and temperate waters of Western Australia. In addition, taxonomic and ecological studies on barnacles, records in museum collections and information from recent expeditions, have suggested a general pattern of distribution for Australian barnacles. This study also aims to compare the composition of the Australian barnacle fauna with those of the Indian Ocean, Indonesia/Malaysia and the western Pacific Ocean, as well as discuss the latitudinal and depth associated patterns related to species richness. Introduced barnacle species, whose geographical distributions have been altered through human activity (fouling species and species associated with introduced fauna) are also considered.

Jones, J.B.¹ and Evans, L.H.²

¹Fisheries WA, Fish Health Unit, c/o Animal Health Laboratory, 3 Baron-Hay Court, South Perth WA 6151, Australia ²Aquatic Science Research Unit, Curtin University of Technology, Bentley WA 6102, Australia

Histopathology of pesticides, metals and related chemicals on decapod crustaceans

There is a large volume of literature on the toxic effects of chemicals on decapod Crustacea. However, while showing a causal relationship between chemical concentration and morbidity/mortality, such information is not of itself diagnostic. This causes difficulties for those who have to arrive at a diagnosis based on clinical signs and histopathology and who need to separate the effects of environmental contaminants from the effects caused by the presence of disease agents. This paper reviews both published and unpublished data on histopathological changes associated with common chemical toxins affecting decapod crustaceans and compares the responses seen to those associated with infectious processes.

Jones, M.B. and Depledge, M.H.

Plymouth Environmental Research Centre (Department of Biological Sciences), University of Plymouth, Drake Circus, Plymouth PL48AA, Devon, UK

Biomarkers, crustaceans and environmental pollution

Over the past 30 years, individual crustacean responses to chemical pollutants have provided clear understanding of the mechanisms by which specific biochemical and physiological systems (respiratory, cardiovascular, hormonal etc) are impacted. However, it is often difficult to identify the ecological relevance of these measures from single systems and it is timely to assess critically whether we are measuring the appropriate biological responses to predict the environmental consequences of chemical pollution. We argue that a holistic view of the integrated response of individuals to pollution allows not only better prediction of the likely effects of chemicals on the environment but also identifies the key diagnostic parameters that are surrogate measures of whole organism impacts and effects. In this presentation, we illustrate this approach using various integrated measures of biological responses (behaviour, biomarkers) both singly and in combination.

Kapiris, K.^{1, 2} and Thessalou-Legaki, M.¹

¹Departement of Zoology-Marine Biology, School of Biology, University of Athens, Panepistimioupolis, GR-157 84, Athens, Greece ²National Centre for Marine Research, Institute of Marine Biological Resources, Aghios Kosmas, Hellinikon, GR-166 04, Athens, Greece

Variations in the feeding activity of Aristaeomorpha foliacea (Decapoda: Aristeidae)

The feeding activity of the deep-water shrimp Aristaeomorpha foliacea, as indicated by the frequency of empty stomachs, the mean observed stomach fullness and the repletion index [RI = (stomach content weight/ body weight)(100], was studied from samples collected monthly during a one-year survey in the SE Ionian (Mediterranean Sea). The feeding activity varied significantly with time in both sexes. Nevertheless, sex-related differences occurred during summer and autumn, resulting to an overall increase in favour of females. In addition, individual weight was linearly correlated, in both sexes, to stomach content weight but not to RI. Small females (CL<30 mm) showed higher RI than larger females as well as small males. Mean stomach fullness, on the other hand, was in favour of the largest females. The results of the present study are discussed in relation to the existing information on the population biology of the species.

Karasawa, H.¹ and Kato, H.²

¹Mizunami Fossil Museum, Yamanouchi, Akeyo, Mizunami, Gifu 509-6132, Japan ²Natural History Museum and Institute of Chiba, Aoba-cho, Chiba 260-8682, Japan

The systematic status of Miosesarma Karasawa, 1989 with a discussion of adult morphology-based phylogenetic analysis of the family Grapsidae and a review of the fossil record (Crustacea: Decapoda: Brachyura)

The Japanese Miocene genus Miosesarma was originally placed in the grapsid subfamily Sesarminae. Examination of newly obtained specimens shows that the genus has close affinities with sesarmine genera, Helice and Metaplax. Schubart et al. (2000) suggested reclassification of Grapsidae and that Helice and Metaplax were classified within Varuninae by using molecular data. A phylogenetic analysis of 23 grapsid genera is provided based on 43 adult morphological characters. The analysis resulted in a single tree 84 steps long (CI=0.595, RI=0.815, RC=0.485) supporting the monophyly of Plagusiinae, Grapsinae and Varuninae. Our analysis suggests that Sesarminae is polyphyletic and that four genera, Cyclograpsus, Helice, Metaplax and Miosesarma, are derived as the sister to varunines and are removed from Sesarminae to Cyclograpsinae. Palaeograpsus known from the European Eocene is referred to Goneplacidae. During a review of fossil records of Grapsidae, 25 species, 17 genera and 4 subfamilies are recognized as fossils. Three extinct genera do not belong to any subfamily and Plagusiinae lacks fossil records.

Keable, S.J. and Wilson, G.D.F.

Centre for Evolutionary Research, Australian Museum, 6 College Street, Sydney, NSW, 2010, Australia

Morphological character assessment and phylogeny of the Phreatoicidea (Malacostraca: Isopoda)

Extant phreatoicideans show few differences from fossils preserved 325 mybp, however, they are adapted to various freshwater habitats and display considerable morphological variety. Many species are threatened due to their restricted distribution, but management decisions cannot be made without better data. Furthermore, the suborder needs revision because it is more diverse than recognised, existing genera being weakly defined and difficult to identify, and the higher classification is paraphyletic. These problems cannot be addressed without a robust phylogenetic analysis. We report an analysis that extends previous work by including outgroups from outside the Isopoda (Spelaeogriphacea and Tanaidacea) and a revision of morphological characters using scanning electron microscopy (SEM). Cladogram topologies involving various forms of reduction of the mandibular lacinia mobilis (an important character currently dividing the suborder into two families) are presented. Homologies of the antennula articles, pleotelson, pleopod appendix masculina, pereopod I propodal palm setae and uropods are also examined.

Keenan, C.P.¹ and Lavery, S.²

¹Bribie Island Aquaculture Research Centre, Woorim, Qld 4507, Australia. ² Qld Agricultural Biotechnology Centre, University of Queensland, Qld 4072, Australia

Mitochondrial DNA Discrimination of Four Cryptic Species within the Portunid genus Scylla de Haan (Crustacea: Decapoda)

A genetic and morphological study of over 300 mud crab specimens from 33 locations throughout the Indo-West Pacific has demonstrated the existence of four distinct species. Initially, allozyme electrophoresis was used to separate the specimens. Of 36 loci examined, fourteen were monomorphic, 16 polymorphic and 10 showed fixed differences with no evidence of hybridisation, suggesting species level differences. To confirm this interpretation, differences in the mitochondrial DNA of selected samples were studied. Complete, bidirectional sequencing of two mitochondrial genes, cytochrome oxidase I (COI) and 16S rRNA, showed between species variability to be at least ten times greater than within species variability. Between species sequence variability for COI was between 8 and 13% and for 16s averaged approximately 7%. These figures are similar to those observed between species from other crustacean genera. Mean within species variability was 1.29% for COI, and 0.48% for the 16s sequence.

Khan, R., Pung, O. and Spiers, J.

Department of Biology, Armstrong Atlantic State University, Savannah, GA. USA *Department of Biology, Georgia Southern University, Statesboro, GA. USA

Prevalence and distribution of the trematode Microphallus turgidus in grass shrimp (Palaemonetes spp.), and parasite-induced changes in host's locomotion behavior

Grass shrimp, Palaemonetes spp., are common in estuaries and marshes along the east coast of the U.S.A. and serve as second intermediate host for the trematode, Microphallus turgidus. Two grass shrimp species (Palaemonetes pugio and P. vulgaris) from 7 sites in Georgia were surveyed for this parasite. Shrimp (n=1304) were measured, wet body weight recorded, and metacercarial cysts counted. The prevalence of M. turgidus was significantly higher in P. pugio (69%) than in P. vulgaris (24%), as were parasite intensity and density (cysts/g body weight). This may be due to different habitat preferences of the 2 species of shrimp. Parasite-induced changes in shrimp locomotion were analyzed by monitoring swimming and walking behavior. Results showed that, as the number of cysts increased (1-30+), shrimp locomotory activities proportionately and significantly declined compared to unparasitized individuals. Thus, the presence of cysts in abdominal muscles may interfere with the locomotion of the shrimp.

Kihara, T.C., Rocha, C.E.F. and Santos, C.

Departamento de Zoologia, Universidade de São Paulo, São Paulo, Brazil

A new species of Catinia (Copepoda, Poecilostomatoida, Catiniidae) associated with mud shrimps, Axianassa australis (Crustacea, Decapoda, Thalassinidea), from Brazil

A new species of Catinia was collected from external surface of carapace and uropods of several mud shrimps in the intertidal zone of Araçá Beach, state of São Paulo, Brazil (23 48'50''S, 45 23'48''W). The new species shares with Catinia plana the structure of the oral appendages, the setal formulae of the swimming legs, a robust pedunculate sucker on the antepenultimate segment of the second antenna, and the absence of the maxilliped in adult females. However, the two species can be separated by body shape and by the armature of the antenna, maxilla, and maxilliped of the males. This is the first record of Catinia since the genus was established based on material from Baie de Morgat, France, in 1957.

Kihara, T.C.¹, Huys, R.² and Rocha, C.E.F.¹

¹Departamento de Zoologia, Universidade de São Paulo, São Paulo, Brazil ²Department of Zoology, The Natural History Museum, London, UK

First record of Tachidiidae (Copepoda, Harpacticoida) in the Southern Hemisphere

During studies on the diversity of meiobenthic marine harpacticoid copepods, a new representative of the family Tachidiidae was found in Flamengo Bay, Ubatuba (23 30'S, 45 05'W) on the northern coast of São Paulo state, Brazil. The specimens were collected in fine sand at 7 m depth. Tachidiids, typically inhabiting fine muddy sediments, are good indicators of heavy organic pollution. The new genus shares with Microarthridion the reduced antennules, morphology of the maxilliped claw, swimming legs with the first segment of the endopod reduced, absence of sexual dimorphism, leg 5-bearing somite without integumental windows, and the morphology of leg 5 in both sexes. Nevertheless, the new genus can be easily distinguished from others in the family by the reduction in segmentation and ornamentation of the swimming legs. This is the first record of the family Tachidiidae in the Southern Hemisphere.

Kim, S.H.¹, Park, J.-K.¹, Koo, H.² and Kim, W.¹

¹School of Biological Sciences, Seoul National University, Seoul, Korea ²Department of Biological Science, Sangji University, Wonju, Korea

Three morphotypes of the snapping shrimp found in the burrows of mud shrimp, Upogebia major (De Hann)

Previously, three alpheid species have been recorded from the burrows of mud shrimp, Upogebia major (De Hann): Stenalpheus anacanthus Miya, 1997 (from Japan), Chelomalpheus koreanus Kim, 1998 (from Yellow Sea of Korea), and Cavipelta yamasshitai Hayashi, 1998 (from Japan). Although different generic names have been proposed, it seems that all three species are congeneric in terms of sharing a suit of characters such as the presence of a notch on the inferior margin of carapace and roundly elongate immovable teeth on the transverse suture of the uropodal exopod. This study also suggests that morphological differences found between two Japanese forms can fall into the range of conspecific variations. However, Chelomalpheus koreanus shows a profound morphological distinction from either of Japanese forms in uropodal structures. More recently, we discovered a new form differed from previously recorded congeners. Morphological discontinuities among three alpheid morphotypes are here presented, with a brief emphasis on ecological features.

Koenemann, S. and Schram, F.R.

Institute of Biodiversity and Ecosystem Dynamics, Mauritskade 57, 1090 GT Amsterdam, The Netherlands

New tools and methods: The application of developmental data in phylogenetic systematics

Of late, the field of developmental genetics has increasingly stimulated innovation in studies of animal phylogenetics. As a new source of information, it enables us, at the very least, to evaluate hypotheses of morphological homologies. For example, the patterning of developmental gene expressions related to the ontogeny of limbs can help evaluate various scenarios of crustacean evolution. However, genetic developmental data are available presently for only a few, selected crustacean taxa. The amount of data is not sufficient to directly perform large-scale phylogenetic reconstructions. Nevertheless, it is possible to apply another source of developmental data to comprehensive phylogenetic analyses. The occurrence of developmental events during ontogenesis is well documented for a vast number of crustaceans. The chronological appearance of these events can be treated as relative sequences that show characteristic patterns for each taxon. Subsequently, the algorithmic comparison of chronological sequences can be used to generate a phylogenetic tree.

Konishi, K.¹, Matsumoto, T.¹. and Murakami, K.²

¹National Research Institute of Aquaculture, Nansei, Mie 516-0193, Japan ²Minami-Izu Station, Japan Sea-Farming Association, Minami-Izu, Shizuoka 415-0156, Japan

Morphological notes on the mouthparts of decapod larvae

In decapod larvae, the functional morphology of mouthparts has been poorly understood in spite of many previous larval studies. We examined larval mouthparts, consisting of labrum, mandibles, hypostome and maxillules, in main decapod groups and discussed on its function and morphology. Among decapod larvae, there are two remarkable examples in the morphology of mouthparts: i.e., those of palinurid phyllosoma and some thalassinid zoeas. Distal part of andibular processes of phyllosoma is covered by large labrum and hypostome. It is suggested that this unique feature of phyllosomal mouthparts is related with their specialized feeding behaviour: chewing and swallow of prey organisms. In laomediid and thalassinid zoeas mandible and hypostome are sickle-shaped and are extremely asymmetric form in decapod larvae. At present, however, no information is is available about feeding mechanisms of these larvae.

Koslov, Oleg V.

Siberian Research and Project-Construction Fishery Institute, Kurgan Branch, Kurgan, Russia

Crustaceans in ecology-economic systems of south part of West-Siberian plane lakes

Estimating typology of lake ecosystems of the south of the West-Siberian plain, on the basis of mineralization and zooplanktocenosis, is possible to allocate lakes with predominance of Cladocera (1-15/ml), Gammarus lacustris (5-25/ml), Calanoida (15-35/ml) and Artemia salina (>25/ml). In 2000 in territory of region for production of crustaceans, 49 reservoirs (in 1999 - 30 lakes, in 1998 - 24 lakes) were used, and the basic direction was the production G. lacustris (35 lakes, total 662 tons) and eggs A. salina (10 lakes, production 289 tons), the fishing Daphnia sp. is begun. The development of fishing is determined by growing world demand and the influence of these processes on development of a social and economic system. In Western Siberia people, especially in village settlements, are connected to ecosystem components. The development of populations of planktonic crustaceans occurs in natural conditions at use abiotic resources of lakes, which can be economically appreciated conditionally enough. The ecology-economic estimation of crustacean populations should be made from the point of view of an integrated resource, when use of one of components of resource potential has an effect for preservation of a condition and structure, and as to dynamics of other components. In modern economic conditions it is necessary to take into account the differential rent, which is connected with a ecosystem location, its importance for development and stability of social and economic components, ease of production and riches of crustacean resources.

Krapp-Schickel, T.

Museum A. Koenig, D-53113 Bonn, Germany

Revision of the genus Apherusa (Calliopiidae, Amphipoda, Crustacea)

For more than 30 years I have been struggling with the basic Bauplan of the calliopiid amphipod genus Apherusa. My earlier studies of so-called 'highly variable species' in the genera Caprella, Stenothoe and Maera have shown, that these often consist of groups of closely related species with very small, but constant specific differences. In Apherusa repeated study of specimens of different age and localities has revealed a similar scenario. The classical methods of dissecting and drawing all parts of specimens of different sex and age were supplemented with SEM-pictures of surface structures and of fully developed penis-papillae. These latter revealed that some specimens, otherwise similar to females, in fact were mature males of a different species, and also that the form of these papillae can be a valid and valuable specific character, hitherto neglected by amphipod taxonomists. A cladistic analysis using PAUP gives a first glimpse of the phylogeny of this group of calliopiid species.

Lemaitre, R.¹ and Tudge, C.C.²

¹Department of Systematic Biology, National Museum of Natural History, Smithsonian Institution, Washington, D.C. 20560-0163, USA ²Biology Department, American University, 4400 Massachusetts Ave, NW, Washington DC 20016-8007, USA

Sexual tubes in hermit crabs of the family Paguridae: a review of their morphology

Sexual tubes have been known in male hermit crabs for more than 100 years, but only scant information exists on their structure, function, and evolution. These tubes are believed to be extensions of the vas deferens arising from the gonopores, and used in the transfer of spermatophores. Although not unique to the family Paguridae, sexual tubes are extremely diverse in this family where they are present in 32 (50%) of the currently recognized 64 genera. Tube characteristics are a major criteria currently used to define genera. The tubes vary remarkably in form and shape (short, long, filamentous, coiled), and symmetry, and often are present only on one side. Aspects such as their cellular composition, mobility, and mode of use, are unknown. This study presents a review of the morphology of male sexual tubes in the Paguridae, and investigates their morphology, ultrastructure and possible function based on observations in selected genera.

Lemos, D.¹, Hernandez, P.², Navarrete, A.² Sanchez, A.² and Garcia-Carreño, F.L.²

¹Instituto Oceanográfico, University of São Paulo, São Paulo (SP), Brazil ²Centro de Investigaciones Biológicas del Noroeste, La Paz (BCS), Mexico * Present address: University of Mogi das Cruzes, Mogi das Cruzes (SP), Brazil

Ontogenetic variation in digestive proteinase activity, RNA and DNA content of larval and postlarval shrimp Litopenaeus schmitti (Crustacea: Decapoda: Penaeidae)

Proteinase (endopeptidase), trypsin and chymotrypsin activities, RNA and DNA contents were examined throughout the ontogenetic development of cultured Litopenaeus schmitti. Whole individuals from larval and postlarval stages, and adult hepatopancreas were homogenised and assayed for activity quantification. Proteinase activity of different life stages was characterised by substrate-SDS-PAGE. Specific inhibitors for trypsin (TLCK) and serine proteinases (PMSF) were added to enzyme extratcs to identify activity zones of these enzymes in gels. Nucleic acids were determined in larval and postlarval stages. Protein-specific activity of total proteinases and trypsin presented higher values in Nauplius IV (N IV), Protozoea I (PZ I) and PZ III compared to the remaining stages, while chymotrypsin activity peaked in N IV and PZ III. Enzyme activity was decreased in Egg, early Nauplius, Mysis and postlarval stages. Different proteinase patterns were observed in SDS-PAGE during the ontogenetic development. Active bands of 15.5, 15.9, 20.9, 21.8, 24.0, 27.9, 30.4, 33.5, 35.5, 39.2 and 48.3 kdaltons were detected in the adult hepatopancreas. In the course of development, proteolytic activity appeared in N IV, and intense bands of 15.9, 18.0 and 20.9 kdaltons were found up to Mysis (M III). A band of 39.2 kdaltons was present between N IV and M I, and between PL II and PL IV. Most inhibited bands performed as serine proteinases and only two adult bands (15.5 and 15.9 kdaltons) were inhibited by TLCK. Both RNA and DNA contents (µg mg^–1 of fresh weight) reduced with development from Egg until PZ III, increasing afterwards until PL IV. RNA:DNA ratios increased from Egg, reached the peak in PZ I, decreasing in the following stages until a minimum in M II. A secondary peak was observed in PL III followed by reduction in PL IV. The variation in enzyme activity indicates different strategies of energy use throughout the development. Higher enzyme activity combined with increased RNA:DNA in protozoeal stages denote intense food energy utilisation and accumulation into growth. The shift in energy strategy during ontogeny is accompanied by variation in proteinase characteristics as observed in other penaeid species.

Lemos, D.¹*, Salomon, M.², Gomes, V.¹, Phan, V.N.¹ and Buchholz, F.²

¹Instituto Oceanográfico, University of São Paulo, São Paulo (SP), Brazil ²Biologische Anstalt Helgoland, Alfred-Wegener-Institute Foundation for Polar and Marine Research, Helgoland, Germany * Present address: University of Mogi das Cruzes, Mogi das Cruzes (SP), Brazil

Citrate synthase and pyruvate kinase activities during the early life stages of the shrimp Farfantepenaeus paulensis (Crustacea, Decapoda, Penaeidae): effects of ontogenetic development, acclimation temperature and nutritional condition

The activities of metabolic enzymes citrate synthase (CS) and pyruvate kinase (PK) were determined throughout the larval and postlarval stages of reared Farfantepenaeus paulensis. Individuals were subjected to different temperature (20 and 26 C) and nutritional (fed or unfed) regimes. Oxygen consumption (QO₂) and ammonia excretion rates were measured for comparison with enzyme activities. Both temperature and nutritional state did not affect the ontogenetic trend of CS and PK activity, from the Protozoea (PZ) until the Postlarva (PL). Parallel to QO₂, weight-specific activity of CS decreased throughout the ontogenetic development. PK activity increased from Mysis I (M I), reaching a pronounced peak in PL V-VI, followed by a further decrease in PL XII-XIV. Temperature decrease significantly affected metabolic rates and enzyme activities. Higher excretion was observed in M III, PL V-VI and PL XII-XIV, resulting in reduced O:N ratios in these stages. At 20 C, QO₂ was lower in PZ II and M I compared to rates at 26 C while no difference was detected in the following stages at either temperature. Significantly higher CS and PK activities occurred in M III, PL V-VI and PL XII-XIV at 20 C. Fasting did not produce significant effects on CS and PK in the majority of stages. Linear regressions between individual enzyme activities and dry weight produced slope values (b) of 0.85-0.92 for CS and 1.1-1.2 for PK, with significantly higher b at 20 than at 26 C for both enzymes. Weight-specific CS activity correlated positively with QO₂ at both temperatures, showing the potential for the applicability of an indicator of metabolic rate in F. paulensis. Due to the role of CS and PK in aerobic and anaerobic metabolism, respectively, the variation in their activities appears to be related to metabolic adaptations throughout specific ontogenetic events of F. paulensis early stages.

Lemus, M.¹, Chung, K.S.², García, E.³ and Marín, B.²

¹Departamento de Biología, Escuela de Ciencias, Universidad de Oriente, Cumaná, Venezuela ²Instituto Oceanográfico de Venezuela, Universidad de Oriente, Cumaná 6101, Venezuela ³Departamento de Biología de Organismos Universidad Simón Bolívar, Caracas, Venezuela

Reproductive biology of Emerita portoricensis (Crustacea: Decapoda) in the San Luis Beach community, Sucre State, Venezuela

We evaluated the reproductive cycle of the mole crab (Emerita portoricensis) and the effects of the environmental parameters on the process of egg maturation. The mole crab were collected in the community of San Luis Beach, located in Sucre State (10 28 N, 64 10 W) from January 1997 to January 1998. The adult females were classified according to the macroscopic analysis of the egg mass. The gonadosomatic and hepatosomatic indices were determined. The presence of the four stages of egg development throughout the whole year suggests a continuous ovigerous development, the maximum development being during the months of August and December. The results of the present investigation demonstrate that rainfall and upwelling seem to affect the egg maturation cycle of the species.

Leung, T.Y.

The Swire Institute of Marine Science, Department of Ecology and Biodiversity, the University of Hong Kong, Cape d' Aguilar, Shek O, Hong Kong

The effects of water temperature and food on the reproductive biology of Ibla cumingi (Cirripedia: Pedunculata) in Hong Kong

Ibla cumingi is one of two stalked barnacles recorded from the eulittoral zone in Hong Kong. The species commonly inhabits inside rock crevices on sheltered to semi-exposed shores. Gravid individuals can be recorded almost throughout the year with peaks (> 60%) recorded in spring and late summer and minima (< 10%) during winter. Water temperature and food availability have been shown to influence the reproduction of many species of barnacles. Experiments on the effects of water temperature (winter, spring and summer) and different food rations (low, high and excess) on the reproduction of I. cumingi, were carried out in January 1999. The results show that the production of larvae was related to seawater temperature, but apparently not related to the availability of food. It is suggested that higher temperatures can enhance brood size and numbers of I. cumingi.

Levings, A.

Deakin University, Warrnambool 3280, Australia

Movement and Distribution of the Giant Crab Pseudocarcinus gigas off southern Australia

The bryozoan limestones which contain fossil relicts of giant crabs were deposited in an environment analogous to present day conditions at the edge of the continental shelf where this species occurs in greatest abundance. his study has examined 80,000 crabs and tagged 18,000 along the southern Australian continental margin from Margaret River (WA) to St Helens (Tas). The 1755 recaptures reflect specific patterns of movement which are advantageous for survival and reproductive success. The crabs forage into the current within a niche where the boundaries are defined by availability of food resources and water temperature. These are the forcing influences which despite the crabs nomadism lead to aggregation at certain locations and times in a seasonal cycle.

Lewis, D.¹, Neil, D.M.¹, Holmes, J.M.² and El Haj, A.²

¹Institute of Biomedical and Life Science, University of Glasgow, Glasgow, Scotland, UK ²School of Postgraduate Medicine, Keele University, UK

The effect of rearing temperature on the swimming performance of postlarval European lobsters, Homarus gammarus.

It is standard practice in lobster hatcheries to elevate rearing temperatures, to accelerate the growth rate of the larval and postlarval stages. However, the consequences of raising water temperature for the muscle physiology and performance of these lobsters once released back into the marine environment is not known. Therefore, in this study groups of post-larval European lobsters, Homarus gammarus were raised at 11, 15 and 19 C from post-larval stage 6 (approximately 3 months old) to 18 months. Full records of their times of moulting and morphometric measurements were maintained, and their swimming performance at the temperatures of rearing were measured at regular intervals. These results have been related to the age, moult stage and body size of the animals, and to the phenotypic properties of their muscle fibres and the expression of genes for key sarcomeric proteins. As well as demonstrating size-dependent kinematics, their swimming abilities reflect a metabolic compensation for the temperature of rearing. Funded by the UK NERC DEMA Thematic Programme.

Li, F.H., Xiang, J.H., Zhou, L.H., Wu, C. G. and Zhang, X.J.

Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, P. R. China

Optimization of Triploidy Induction by Heat Shocks in Chinese Shrimp Penaeus chinensis.

Chromosome manipulation for economic marine animals will play an important role in aquaculture. Shrimp has special reproductive characteristics. The development of fertilized eggs is very asynchronous. Triploid shrimp was induced by heat shocks and the optimal inducing condition was screened at different spawning temperature. Triploid induction rate for each treatment group was evaluated by flow cytometry at nauplius stage. The highest triploid induction rate for Penaeus chinensis can reach more than 90%. The starting time for each treatment was very pivotal to the inducing results. The best treatment condition for triploid shrimp in Penaeus chinensis was discussed. Triploid rate at embryo stage and nauplius stage was compared. The result showed that heat shock is a very effective way to induce triploids in Penaeus chinensis. It will easily be used at large scale and brings no harmful effect to the environment comparing with chemical treatment.

Lima, M.C.G.¹ Valentin, J.L.¹ and Zeidler, W.²

¹Departamento de Biologia Marinha, Instituto de Biologia, UFRJ, Rio de Janeiro, Brasil ²South Australian Museum, Adelaide, Australia

Hyperiid (Crustacea: Amphipoda) from a collection having the Subtropical Convergence (Atlantic Ocean) as its southern boundary

A total of 128 zooplankton samples, in the upper 200 m layer, were collected using a cylindric-conical net (250 µm and 80 cm mouth diameter) from 26 48.3' to 30 39.3'S; 44 21' to 56 54'W, during the Winter and Autumn Seasons of 1977, in the Brazilian, Uruguayan and northeastern Argentinean coast (CONVERSUT I Cruise). A total of 97 species were found. The more abundant were Themisto gaudichaudii Guérin (54%), T. australis (Stebbing) (16%) and Lestrigonus bengalensis Giles (10%); the more frequent were Hemityphis tenuimanus Claus (46%), L bengalensis (41%), Brachyscelus crusculum Bate (39%) and T.gaudichaudii (39%). Thirty-four species are new records for the area. The occurrence and distribution, according to the 6 water masses present in the region, and their presence either in the coastal or oceanic areas are discussed. Data for temperature, salinity, depth, density, diversity and species richness are analysed using multivariate techniques: Twinspan (PCORD) and Principal Component Analyses (PCA).

Lindhjem, P., Bolton, P., Jones, E., Lukehurst, S. and Knott, B.

Zoology Department, The University of Western Australia, 35 Mounts Bay Rd Crawley, WA 6009, Australia

Morphological comparison of gills from three species of Cherax indigenous to Western Australia

The trichobranchiate gills of the freshwater crayfish Cherax tenuimanus (from permanent rivers) bear many filaments which function in either an ion-transporting or respiratory capacity. Staining gills with silver nitrate and visualising these with a backscattered electron dectector using scanning electron microscopy highlights intricate staining patterns which indicate areas of epithelia involved in ion-transport. A comparison of the morphology and putative function of another two Cherax species, Cherax quinquicarinatus, (from freshwater streams) and Cherax preissi (from temporary swamps), with those of Cherax tenuimanus to detect what influence habitat may have on the number, detail and distribution of filament types on the main gill stem.

López Greco, L.S., Lavolpe, M. and Rodríguez, E.M.

Department of Biological Sciences, University of Buenos Aires, Argentina

Embryogenesis and hatching of the estuarine crab Chasmagnathus granulata (Grapsidae) exposed to copper

The effect of copper on embryo development and hatching was assayed in the crab C. granulata by two experiments. First, ovigerous females whose embryos were at recent (<1 day), early (4-5 days) or mid (9-10 days) stage of development, were exposed to a copper solution of 0 (control) or 1 mg/L, and the percentage of hatched larvae or egg lost was determined. In the second experiment, mid ovigerous females were exposed to a copper solution of 0 (control), 1 or 2 mg/L, under two photoperiods (14:10 and 0:24, light:darkness). The morphological abnormalities of the hatched larvae were recorded. Main effects of copper were: total lost of eggs in recent ovigerous females at early development, significant egg lost in early and mid ovigerous (especially at time of hatching), asynchronous hatching and morphological abnormalities, mainly related to underdeveloped and depigmented eyes. Control larvae hatched in 0:24 photoperiod regime also showed eye depigmentation.

Lörz, A.N.

Zoological Institute and Zoological Museum, Martin-Luther-King-Platz 3, D-20146 Hamburg, Germany

Low diversity of spongicolous Amphipoda (Crustacea) observed in the Antarctic autumn

Sponges represent a major component of the Antarctic zoobenthos. They are known to act as hosts for several invertebrates. In the present investigation a total of 1193 specimens of Amphipoda living in the sponge tissue of three species of Demospongiae were observed. The sponges were collected in the Weddell Sea and at the Antarctic Peninsula in April, during the Antarctic autumn 2000. The population density, species richness, composition, and reproductive biology of the spongicolous Amphipoda was studied. More than 40 individuals were collected per 1000 cm³ sponge tissue. Females of all species had eggs or embryos in their marsupia. Interestingly, their young will be released - even though most of the studied species are filter feeders - in the Antarctic autumn and winter. Spongicolous inquiline Amphipoda may therefore not be influenced by the seasons as much as their free living relatives.

Lowry, J.K.

Division of Invertebrate Zoology, Australian Museum, 6 College St., Sydney, NSW 2010, Australia

Marine scavenging guilds: the peracaridan component

Marine invertebrate scavenging guilds include groups such as amphipods, copepods, decapods, gastropods, isopods, leptostracans, ostracods and polychaetes. The composition and structure of these guilds has not been considered in most parts of the worlds oceans. Based on the literature and new information from eastern Australia, the contribution of peracaridan crustaceans to these guilds is examined. The main peracaridan scavengers are lysianassid amphipods and cirolanid isopods. Generally cirolanids tend to dominate scavenging guilds in shallow warm water and lysianassids tend to dominate guilds in shallow colder water. In the deep sea there are trends towards gigantism in isopods and amphipods. There are indications that isopods may be important deep water scavengers in the Indian Ocean and amphipods may be more important in the North Pacific and Atlantic Oceans.

Lowry, J.K.

Division of Invertebrate Zoology, Australian Museum, 6 College St., Sydney, NSW 2010, Australia

The role of interactive databases in modern taxonomy

Traditional taxonomic methods often fail current needs. Taxonomy for taxonomists is difficult for non-taxonomists to use. Description of biodiversity is more critical than ever. Habitat loss, large-scale pollution and exotic species introductions make the need for modern faunal descriptions and fast, reliable identifications more important than ever. Identification problems for non-taxonomists include large faunal diversity, scattered literature which is difficult to find and interpret, dichotomous keys which are inflexible and special terminology, which has to be understood. The consequences are often identifications at a level higher than species, which means that biodiversity information is lost and important studies achieve less than their potential. Taxonomists need to provide easier, more convenient information and identification systems for other biologists. Databases such as DELTA offer advantages such as multiple uses of morphological data for descriptions, illustrated, interactive identification systems and generation and management of phylogenetic analyses. They also provide alternative language versions. Web based projects such as crustacea.net provide an opportunity for cooperative effort among international scientists to describe local and world-wide faunas which are freely available to anyone on the net.

Lubzens, E.¹, Avarre, J.-C.¹ and Tietz, A.²

¹Israel Oceanographic and Limnological Research, Haifa 31080, Israel and ²Dept. of Neurobiochemistry, Tel-Aviv University, Tel-Aviv 66978, Israel

Accumulation of lipids in developing oocytes of a marine shrimp

Developing oocytes of marine shrimp accumulate significant amounts of lipids, including highly unsaturated fatty acids (HUFA) that are not synthesized within the ovary. These originate from ingested food either directly or after storage in the hepatopancrea, and must be transported via the hemolymph to ovaries. Three lipoproteins were identified in the hemolymph of vitellogenic females, belonging to the High Density Lipoprotein fraction [LP1 and vitellogenin (VTG)] or the Very High Density Lipoprotein fraction containing the clotting protein (CP). While all lipoproteins contain HUFA, the LP1 was found to carry relatively more lipids than the VTG or CP, suggesting that it most likely serves as the main transporter of lipids to ovaries. The relative contribution of LP1, VTG and CP to accumulation of ovarian lipids has to be fully elucidated. As the LP1 and CP also function in the immune response system, changes in hemolymph lipid levels during vitellogenesis after an induced infection are being investigated.

Lynn, J.W.

Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, USA

Extracellular coat formation in the Penaeoidea

Penaeid shrimp eggs undergo a series of post spawning activation events including jelly layer (JL) formation from stored extracellular precursors and assembly of a hatching envelope (HE). JL precursors are rod-like structures in large, extra-oocytic surface crypts separated from the external media by a thin investment coat. Seawater contact triggers a massive precursor release and transformation into a transient, transparent JL. Precursor release and transformation are Mg but not Ca dependent, are sensitive to serine protease inhibitors, and, for Penaeus aztecus, comprise a glycoprotein (70% protein, 30% carbohydrate) rich in aspartic acid and glycine but with low ratios of histidine, methionine and arginine. JL formation is followed by exocytosis of cortical vesicles involved in the assembly of a primary HE which persists until hatching. Potential JL roles include transient mechanical and antimicrobial protection and involvement in sperm-egg interactions, whereas HE formation provides a long lasting protective environment for embryonic development.

Lyskin S.A. and Britayev T.A.

A. N. Severtsov Institute of Problems of Ecology and Evolution of Russian Ac. Sci., Leninski prospect 33, 117071, Moscow, Russia

An association of symbiotic crab Lissocarcinus orbicularis Dana, 1852 (Decapoda, Portunidae) with tropical holothurians

Lissocarcinus orbicularis Dana, 1852 is obligatory associated with Holothuridae, Stichopodidae and Synaptidae. In Vietnam these crabs were found on 6 species of holothurians. Prevalence varied from host to host and site to site from 0 to 85,7%. Hosts mostly carried single crab. The preferable location was anterior end of holothurians, including oral cavities. Since the crabs feed on small bottom copepods and molluscs, the location on the host body is likely to be connected with feeding activity of holothurians, which turn over the sediment, uncovering benthic animals. 8% of crabs carried externas of rizocephalan parasite Heterosaccus ruginosus. The crabs breed at all seasons of the year. The findings of megalopae on holothurians indicate the settlement of symbionts directly on their hosts. Coloration of the crabs corresponds to that of hosts. Associations between L. orbicularis and holothurians can be considered as commensalism.

Maas, Andreas and Waloßek, Dieter

Section for Biosystematic Documentation, University of Ulm, Helmholtzstraße 20, D-89081 Ulm, Germany

Monophyly of Phosphatocopina revisited

Phosphatocopina are not ostracods but the sister group of Eucrustacea. Their autapomorphies are a specifically shaped bivalved head shield with a straight simple hinge furrow, a small antennula consisting of only a few segments, and the protopod of antenna and mandible being the product of fusion of coxa and basis (basipod). Ontogeny of Phosphatocopina starts with a larva with four pairs of limbs (head larva). The postmandibular limbs are similar to each other and comprise a basipod with a setiferous endite medioproximally (proximal endite) and a three-segmented endopod. The exopods develop from multi-annulate rami into flatten plates with marginal setation. The phosphatocopine species are traditionally assigned to two different groups. An element within the dorsal hinge area, the interdorsum, is always present in hesslandonid species but is missing in vestrogothiid species. The interdorsum is interpreted as another autapomorphy of Phosphatocopina that is reduced in the stem species of the vestrogothiids.

Maiorano P.¹, Kapiris K.², D'Onghia G.¹, Mytilineou Ch.², Tursi A.¹ and Kavadas S.²

¹Department of Zoology, University of Bari, Via Orabona, 4 - 70125 Bari, Italy ²National Centre for Marine Research, Aghios Kosmas, Hellinikon, 16604, Greece

Comparative depth and size distribution of Aristaeomorpha foliacea (Risso, 1827) and Aristeus antennatus (Risso, 1816) between two areas with different fishing impact in the Eastern-Central Mediterranean

Data on the deep-sea shrimps Aristaeomorpha foliacea and Aristeus antennatus were collected during two trawl surveys (August and September 2000) carried out in two areas of the Ionian Sea (Eastern-Central Mediterranean) with different fishing impact: one offshore the south-eastern Italian coast, the other offshore the northern Greece. The sampling was carried out between 300 and 1200 m of depth by using a professional fishing vessel equipped with bottom trawl net. A. antennatus showed a deeper distribution than A. foliacea in both areas. The former was more abundant than the latter in the Italian waters and vice versa in the Greek area. Sex ratio was around 1:1 in A. foliacea and significantly in favour of females in A. antennatus in each study area. Differences in the size structure were detected between the two areas. The results are discussed considering the different fishing impact as well as the depth distribution of the species and the environmental conditions in the two investigated zones of the same basin.

Malek, M.¹ and Sari, A.²

¹ Department of Biology, Faculty of Science, University of Tehran, Tehran-Iran ² Department of Biology, Faculty of Science, University of Tehran, Tehran-Iran

Occurrence of Maritrema arenaria (Digenea: Microphallidae) in the acorn barnacle, Balanus perforatus (Cirripedia: Balanidae) from south-west Wales

During the course of study on reproductive biology of barnacles, samples of Balanus perforatus were collected monthly at lowest low water of spring tide by chiselling off the specimens from bedrock at Rhossili, Kitchen corner, from January 1994 to December 1995. After dissection, metacercarial cysts of a digenean parasite were found in the outer wall of the gut. Cysts were excysted and then metacercaria were transferred to culture medium in order to get adult fluke for species identification. This is the first record of the digenean parasite (Maritrema arenaria in the acorn barnacle (Balanus perforatus). The seasonal variations in the abundance and prevalence of infection as well as variation of these with tidal level and barnacle scutum lengths are discussed.

Mantelatto, F.L.M. and Domiciano, L.C.C.

Departamento de Biologia, FFCLRP, Universidade de São Paulo, Ribeirão Preto, SP, Brasil

Shell utilization pattern by Paguristes tortugae (Diogenidae) from Brazil: natural habitat and laboratory preference

The objective of this study was to characterize the pattern of shell utilization and preference by Paguristes tortugae, from infralittoral areas of Anchieta Island. Specimens were collected monthly (January to December 1998) by scuba diving. The animals and the shells were measured and weighed. The choice experiments were conducted in a glass aquarium where the animals were placed naked with a large number of shells of appropriate sizes. After 72h the animals and chosen shells were checked. The preferred shell type and size were determined by regression analysis. In the field, the shells more occupied were Pisania auritula, Cerithium atratum, Morula nodulosa and Leucozonia nassa, respectively. During laboratory experiments Paguristes tortugae showed significant preference for L. nassa and C. atratum. The shell selection by P. tortugae did not follow the same pattern of shell-type occupation in the field, probably in function of the interspecific competition.

Mantelatto, F.L.M. and Meireles, A.L.

Departamento de Biologia, FFCLRP, Universidade de São Paulo, Ribeirão Preto, SP, Brazil

Pattern of shell occupation by the hermit crab Pagurus brevidactylus (Paguridae) from Anchieta Island, Brazil

The purpose of this study was to characterize the pattern of shell occupation by P. brevidactylus, from infrallitoral area of Anchieta Island, Ubatuba, São Paulo. The specimens were collected monthly (January to December 2000) using scuba dive. The hermit crabs were sexed, weighed and measured on the basis of the shield length (SL). The occupied shells were identified, measured, weighed, and the internal volume (IV) was calculated. A total of 634 males, 197 non-ovigerous females, and 697 ovigerous females were analyzed. Shells of 16 gastropod species were occupied, and Cerithium atratum (48%) and Morula nodulosa (42%) were the most occupied ones. The best association between the hermits and the most occupied shells was SL versus IV (IV = 0.010 SL3.40, r2 = 0.69, and IV = 0.014 SL2.89, r2 = 0.70, respectively). The pattern of shell occupation by P. brevidactylus probably occurs in function of shell availability and internal volume selectivity.

Mantelatto, F.L.M., Faria, F.C.R. and Garcia, R.B.

Departamento de Biologia, FFCLRP, Universidade de São Paulo, Ribeirão Preto, SP, Brazil

Populational aspects of Mithraculus forceps (Brachyura, Majidae) from infrallitoral of Anchieta Island, Ubatuba, Brazil

The family Majidae constitutes an important group for reproductive and phylogenetic studies. We studied the population structure of M. forceps sampled monthly on Anchieta Island, from January 1999 to December 2000. A total of 68 individuals were collected, with mean size 11,75 ± 3,13 mm of carapace length (CL). The population presented unimodal distribution, and the total sex ratio was 1.4:1 in favor of males. Ovigerous females were captured during all seasons. The relative growth showed a good correlation between carapace length and chelar propodus length (females: CPL = 0.247CL1.46, r2 = 1 and males: CPL = 0.247CL1.46, r2 = 0.91). The puberty molt occurred between 8,3 and 10,8mm CL to females, corroborated by the smaller ovigerous female captured, and between 9.6 and 16.2mm CL to males. The low number of immature individuals in the population studied can be related to the cryptic habit and/or to the precocious sexual maturity.

Mantelatto, F.L.M.¹, Garcia, R.B.¹ and Fransozo, A.²

¹Departamento de Biologia, FFCLRP, Universidade de São Paulo, Ribeirão Preto, SP, Brasil ²Departamento de Zoologia, IBB, Universidade Estadual Paulista, Botucatu, SP, Brazil

Morphometry and sexual maturity of the tropical hermit crab Calcinus tibicen (Diogenidae) from Brazil

Ontogenetic changes in relative growth and biometric aspects were studied in the hermit crab Calcinus tibicen. Specimens were collected at two-month intervals for two consecutive years. A total of 570 individuals were analyzed. Mean animal size (shield length) was 5.14 1.23 mm for males, 4.23 0.79 mm for females and 4.53 0.60 mm for ovigerous females. Sexual dimorphism in chela dimensions was stronger. Differences between males and females were found in left propodus length (LPL) and height (LPH) versus shield length (SL) and wet weight (WW) versus SL relationships. Males showed positive allometry, while juveniles and adult females were isometric for the LPL/SL relationship. The size at which a differentiation occurred in the growth of the chelipeds and in the weight gain of males and females was between 3.0 and 3.2 mm SL, suggesting that the sexual maturity is in synchrony with the puberty molt.

Marsden, Islay, D. and Wong, Carol, T.H.

Zoology Department, University of Canterbury, Private Bag 4800,Christchurch, New Zealand

Effects of sediment contaminants on life-history traits/strategies of amphipod crustaceans

Estuarine amphipods are used in sediment bioassays to determine the toxicity of natural sediments. However, for mildly contaminated sediments, LC50 values often cannot distinguish between those that are toxic and non-toxic. Various life-history traits were measured as biomarkers of environmental stress in the tube-dwelling amphipod Paracorophium excavatum. The population structure of amphipods from clean and contaminated sites were compared and laboratory studies investigated the effects of copper on amphipod growth, fecundity and recruitment. These traits were reduced in sediments with a history of contamination and in copper spiked sediments. However, increased sediment copper concentration did not affect the female biased sex ratio. It was concluded that different growth strategies of male and female P. excavatum could affect population structure within contaminated sediments. These results are discussed in relation to the life history strategies of tube-dwelling amphipods, and their stress responses to contaminants compared with other gammaridean amphipods.

Martin, J. W.¹ and Zimmerman, T. L.¹²

¹Crustacea Laboratory, Natural History Museum of Los Angeles County, Los Angeles, CA USA ²Department of Organismal Biology, Ecology, and Evolution, University of California Los Angeles, Los Angeles, CA USA

Collecting coral reef crustaceans without harming the coral: Preliminary results of the Guana Island (BVI) survey

One of the unfortunate ironies of studying coral reefs is that it is usually difficult to study the reef inhabitants without damaging the reef itself. Much of what we know about coral-inhabiting crustaceans comes from dredging or other coral-damaging activities. We constructed small artificial reef matrices (ARMs) using inexpensive materials commonly available in the tropics (concrete, pvc pipe, cardboard, and other materials) and deployed them around a small Caribbean island for one year at a depth of 10 meters adjacent to patches of coral. We present preliminary findings from harvesting these ARMs. Although not all reef-associated species were represented, as might be expected, the numbers and types of species present on the ARMs have convinced us that this is an inexpensive and efficient way of collecting crustaceans without damaging the adjacent reef.

Martin, Joel W.

Natural History Museum of Los Angeles County, Los Angeles, California 90007 USA

An update on the updated classification of Crustacea project

Subsequent to the classification of Crustacea given by Tom Bowman and Larry Abele in 1982, there have been nearly 200 additional families of crustaceans erected or recognized in the literature. Many of the new families represent discoveries of novel forms, but most are the result of "elevating" previously recognized subfamilies as we continue to expand our understanding and appreciation of crustacean diversity. The "updated" classification attempts to incorporate morphological and molecular data and accommodates all of the new families as well as some higher level taxa. In many ways it is unchanged (many former major groupings are still recognized), but in others it differs appreciably from previous classifications (such as Bowman and Abele, 1982). Salient differences and inherent problems are discussed, as well as the status of the project (when to expect the new classification to be available and in what formats).

Martínez, C.M. and Toral-Granda, M.V.

Marine Research and Conservation Department, Charles Darwin Research Station, Galápagos Islands, Ecuador

Trophic ecology of Panulirus gracilis, P. penicillatus and Scyllarides astori in the Galápagos islands, Ecuador

There are three species of lobsters in the Galápagos islands, the red lobster (Panulirus penicillatus), the green lobster (P. gracilis) and the slipper lobster (Scyllarides astori). Fishing for the three species represents over 60% of the income for the fishers. Despite the economical importance of these species not much biological and ecological work has been done. This study describes the quantitative and qualitative components of the diet and the benthic community that comprises the habitat of the three species. A total of 957 stomach samples of the three species were analysed showing that Malacostraca was the most important item in P. penicillatus, Gastropoda in P. gracilis and Bivalvia and Pisces in S. astori. A large amount of unidentified material, presumably of soft bodied animals, was present in the gut of all three species. S. astori appears to have a subtantially different diet than the two spiny lobsters as shown by indices of dietary overlap. In each species diets varied accordingly to state of egg development (in females), size, depth and season. No significant differences were found in the habitats described in terms of abundance of sessile and mobile benthic fauna, among the three species.

Mashiko, K.

Laboratory of Biology, Teikyo University, Hachioji, Tokyo, Japan

Life history evolution and population genetic structures in three species of the freshwater prawn genus Macrobrachium (Palaemonidae, Caridea)

Among approximately 10 species of the genus Macrobrachium in Japan, M. nipponense, M. formosense and M. shokitai have characteristically slender chelipeds (2nd pereopods), implying their close phylogenetic relationships. Out of them, M. nipponense and M. formosense are ubiquitously distributed in lower course of rivers and spawn many small eggs with normal development of larvae, while M. shokitai, which resides in inland fresh waters on a small island of southern Japan, lays significantly large eggs with extremely abbreviated larval development. The allozyme analysis of 22 gene loci indicated that M. shokitai descended from a common ancestor of the three species to spawn small eggs, with a Nei's genetic distance of 0.68 which corresponds to approximately three million years on an assumptive molecular clock in this group. Genetic diversity (average heterozygosity) in the population of M. shokitai was significantly low, perhaps due to small population size with limited larval dispersal.

McDermott, J.J.

Department of Biology, Franklin & Marshall College, Lancaster, PA, USA

Biology of Chiridotea caeca (Isopoda) in the surf zone of sandy beaches along the coast of New Jersey

Chiridotea caeca inhabits the intertidal zone along the western north Atlantic Ocean from Nova Scotia to Florida where it burrows rapidly into the upper centimeter of sand. The population has been studied periodically from 1987 to 2001. Isopods became ovigerous in December; broods of embryos developed slowly during the winter and reached the first juvenile stages (mancas) which exited the females in May. By July all adults disappear from the population. Mancas (mean length = 2.5 mm) and the second stage (mean 3.4 mm) have morphological characters which distinguish them from one another and from all succeeding stages in the life history. Isopods reached maturity (9 to 15 mm) by November, the females doing so following a maturity molt while in amplexus with males. Maturity was recognized in males and females by presence of the appendix masculina and the oostegites, respectively. Fecundity was positively correlated with body length (17 to 74 embryos/brood; mean 44, N = 147).

McKenzie, K.G.¹, Ferrari, I.², Benassi, G.², Sartore, F.² and Sei, S.²

¹School of Science and Technology, Charles Sturt University, Wagga Wagga, Australia ²Department of Ambiental Sciences, University of Parma, Parma, Italy

Testing the principles of exclusion for Antarctic marine crustacean zooplankton (Ostracoda: Halocyprida)

Distributions of two Alacia species in the Ross Sea, Antarctica, were used to test the principle of exclusion for ostracode marine zooplankton. Statistical treatment of a simple model - based on four stations from the 1987-88 Italiantartide Expedition, collected after the melting of the ice barrier in mid-January 1988 -, indicated that the distributions of abundances/depths are highly significant for the two species (Mann-Whitney test) but not significant between stations (Kruskal-Wallis test). The model was applied to the same species in the Ross Sea Gyre, using data from all stations of the 1994-95 ROSSMIZE Expedition along 175o E. Longitude. Statistical analysis confirmed the previous results both with respect to Alacia abundances/depths and between stations, although these samples were collected in November-December 1994, prior to melting of the ice barrier. We conclude that Alacia species conform to the principle of exclusion; then interpret the distributions of three Metaconchoecia species in the ROSSMIZE samples.

Mclaughlin, Patsy A.¹, Anger, Klaus², Kaffenberger, Antje² and Lovrich, Gustavo A.³

¹Shannon Point Marine Center, Western Washington University, 1900 Shannon Point Road, Anacortes, WA 98221-9081B, U.S.A. ²Biologische Anstalt Helgoland; Stiftung Alfred-Wegener-Institut für Polar- und Meeresforschung, D-27498 Helgoland, Germany ³Centro Austral de Investigaaciones Cientificas (CADIC), CC 92, (9410) Ushusia, Tierra del Fuego, Argentina

Larval and early juvenile development in Paralomis granulosa (Jacquinot) (Decapoda: Anomura: Paguroidea: Lithodidae), with emphasis on abdominal changes in megalopal and crab stages

Morphological variations in the two zoeal stages and megalopa of Paralomis granulosa Jacquinot reared under laboratory conditions are reviewed. Attention is directed to certain aspects of their development not previously considered, and the first two juvenile stages are described and illustrated for the first time. Specific consideration is given to the structural changes in the abdominal tergites during the transformation from megalopa to second crab, and the accompanying total pleopod loss.

Mekhanikova, I.V.¹ and Takhteev, V.V.²

¹Laboratory of Water Animals Biology, Limnological Institute of Siberian Branch of Russian Akademy of Sciences, Irkutsk, Russia ²Department of Invertebrate Zoology, Irkutsk State University, Irkutsk, Russia

Daily vertical migrations (DVM) of amphipods in Lake Baikal: regularities, probable reasons and ecological importance

DVM of baikalian benthic amphipods emerging at night in the pelagial are considered. The DVM intensity much changes depending on lake region, season, weather conditions. Biological sense of migrations obviously unequal at different species. The hypothesis about the protective-food nature of DVM is rejected: majority of individuals, rising in the pelagial, have the empty bowelses; at individuals, remaining at the same time at the bottom, the bowelses are filled by food (detritus and rests of benthic organisms). At the majority species DVM are also not connected with the reproduction and pre-amplexing: juvenile individuals prevail in the migratory complex structure. DVM probably help amphipods by an active movement to obtain a sum of temperatures, necessary for ending of a year's sexual cycle. So, at littoral species with seasonal reproduction is the migratory activity most expressed. At an essential warming of water it is reduced. A mass vegetation of planktonic diatoms oppresses also DVM. Apparently diatoms exert repellent influence on crustacean.

Meland, K.

Department of Fisheries and Marine Biology, University of Bergen, Norway

A combined molecular and morphological approach to the phylogeny and biogeography of the deep sea genus Pseudomma (Crustacea, Mysidacea)

The Pseudomma are hyperbenthic marine mysids, containing 40 species which are distributed predominantly in deeper waters (>500 m) of the North Atlantic, North Pacific and Antarctic. In addition some species have also invaded shallower waters extending their range into coastal waters of Chile and California. The following study presents a species phylogeny of the genus Pseudomma which is based on morphological characters of the compound eyes, cephalic appendages, and the sexually dimorphic features of the male and female pleopods. The morphological phylogeny is compared to phylogenetic hypotheses generated from nucleotide data using a 800-bp fragment of 18S rDNA and a 700-bp fragment of COI mtDNA. This is the first time a combined approach is used to infer cladistic relationships within a mysid genus. Questions concerning evolutionary processes within Mysidacea will also be addressed to explain speciation events and biogeographical patterns found among members of the genus Pseudomma.

Melo, S.G. and Brossi-Garcia, A.L.

Dept. Zoologia - Inst.Bioc. - UNESP - Rio Claro, SP, Brazil

The first juvenile stage of Upogebia paraffinis Williams, 1993 (Decapoda: Thalassinidea: Upogebiidae), obtained in laboratory

This study aims to describe the morphology of first juvenile stages of Upogebia paraffinis Williams, 1993, and to compare them to those of the remaining species in the genus, which have already been studied as U. kempi, U. deltaura and U. stellata. Juvenile of U. paraffinis was obtained in laboratory after the five-zoeal stages and one megalopa stage. They were reared individually in Petri dishes with seawater and sand as substrate, at 32 ppt of salinity and 25 C of temperature. The juvenile stage was reached after 22 to 32 days at larvae hatched and spend in average 4,2 days before the next stage. U. paraffinis juvenile are more developed than those three species. They are differentiated specially due presence of 2-segmented mandible palp in U. paraffinis, 3-segmented in U. kempi and non segmented in U. deltaura and U. stellata. The segmentation of endopod and exopod of maxillipeds can be used as differential too. The size of quelipod differs between species. Others differences can be observed about spines on pereopods, the number of setae on maxillule and maxilla, and on shape or spines on posterior margin of telson.

Melville-Smith, R. and Cheng, Y.W.

Western Australian Marine Research Laboratories, Fisheries Western Australia, P.O. Box 20, North Beach, WA 6020, Australia

Responses of migrating western rock lobsters (Panulirus cygnus) to two different tagging release procedures

In the 1997/98 season, 9,936 migrating sub-legal sized western rock lobsters were tagged in depths of between 0-27, 36-72 and >90 metres. Most lobsters (n=8,831) were brought ashore to be tagged, held overnight in coffs, and released approximately 18 hours after capture in the same depth and general area from where they had been taken. A smaller number (n=1,105) were tagged and released at sea soon after capture. Proportionately more animals tagged at sea were recaptured than those held inshore overnight (P=<0.001). In one tag release location the animals tagged at sea moved significantly further than those tagged ashore (P<0.001), but in a second location there was no significant difference between the two groups (P=0.71). In neither of the two different tagging release procedures was there any significant difference (P=0.6) in the direction of movement followed by the tagged animals, nor were their subsequent growth increments affected (P=0.2).

Miller, A.D., Murphy, N.P., Nguyen, T.T.T. and Austin, C.M.

School of Ecology and Environment, Deakin University, Warrnambool, Australia

More fat on the fire: Increased taxon sampling of decapod crustaceans supports the close affinity of insect and decapod crustaceans using mtDNA sequences

The relationship between crustaceans and insects and the unity of the former group represents two of the most vexatious issues confronting crustacean systematics and are critical to the understanding of arthropod evolution more generally. These controversies have largely arisen as a result of recent phylogenetic studies utilising mitochondrial DNA and protein sequences that indicate that decapod crustaceans are more closely related to insects than they are to branchiopod crustaceans. These studies however are based upon very limited taxon sampling of higher crustaceans. To further address this issue DNA sequences have been obtained from several of the most conserved mtDNA gene regions (12S rRNA, 16S rRNA, COI and Cyt b) from a number decapod species either directly or from GenBank. Phylogenetic analyses of these data with sequences from a range of insect species and two branchiopod species provides further support for the proposition that insects may represent "flying crustaceans".

Morritt, D.¹ and Spicer, J.I.²

¹School of Biological Sciences, Royal Holloway University of London, Egham, Surrey, TW20 0EX, UK ²Plymouth Environmental Research Centre, School of Biological Sciences, University of Plymouth, Drake Circus, Plymouth, Devon, PL4 8AA, UK

Into the groove: the central role of exosomatic water in talitrid amphipods

Arguably the key feature of the amphipod bauplan is the ventral groove (VG) which is believed to be pre-adaptive to a terrestrial existence in the Family Talitridae. The eggs are brooded here and in semi- and euterrestrial species it contains exosomatic water, the composition of which is tightly controlled. We suggest that this exosomatic water plays an essential role in key physiological processes, namely osmoregulation, gaseous exchange and nitrogenous excretion, and is thus central to the success of the group in invading and colonising land. Unfortunately, at present, a rigorous comparative study is hampered by the lack of a well developed talitroid phylogeny. However, we can advance a number of testable predictions for the physiological characteristics associated with the exosomatic water in the VG of species from each of Bousfield's (1984) four eco-morphological groups. These provide a focus for future work on the physiological ecology of land invasion by amphipods.

Morritt, D.¹, Wheeler, J.R.¹, Leung, K.M.Y.¹, Sorokin, N.², Whitehouse, P.², Toy, R.³ Holt, M.⁴ and Crane, M.¹

¹School of Biological Sciences, Royal Holloway, University of London, Egham, Surrey, TW20 0EX, UK ²WRc plc, Henley Road, Medmenham, Marlow, Bucks. SL7 2HD, UK ³Shell Chemicals Ltd, Shell Centre, London SE1 7NA, UK ⁴ECETOC, Brussels B-1160, Belgium

General trends in the sensitivity of crustaceans to pollutants across aquatic environments

Risk assessments for chemicals released into the environment are based on laboratory toxicity test results. These data can be readily accessed through electronic databases. Acute freshwater and saltwater toxicity data for the relatively data rich data sets of 21 common aquatic pollutants were used to construct a species sensitivity distribution (SSD) for each assemblage. Congruence between the two SSDs differed for different chemicals. We examine the contribution of crustacean species to these SSDs and highlight chemicals for which crustacean data have a strong influence on derived hazardous concentrations (e.g. organophosphate pesticides). Differences in toxicity to crustaceans between media are considered: in some cases e.g. heavy metals, the difference can be explained by differences in chemical speciation and / or physiological considerations. We discuss the representation of crustaceans in the data set, consider how this relates to natural assemblages and address the question "Are crustaceans surrogate insects in saltwater risk assessments?"

Mouat, B.¹, Taylor, A.¹, Atkinson, R.J.A.², Bailey, N.³ and Tuck, I.³

¹Division of Environmental and Evolutionary Biology, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow, Scotland, UK ²University Marine Biological Station Millport, Isle of Cumbrae, Scotland, UK ³Fisheries Research Services, Marine Laboratory, Aberdeen, Scotland, UK

Male reproduction - size matters

Determination of size at first maturity in male crustaceans can be very important in fished populations. This paper looks at different definitions of 'maturity' in male Norway lobsters Nephrops norvegicus (Decapoda, Nephropidae), a species that supports a fishery of major importance. Different methodologies for calculating size at first maturity (SOM) are compared. Maturity in male crustaceans can be divided into two main categories: physiological and functional. Physiological maturity describes the size at which the testes of an individual begin the production of sperm whereas functional maturity represents the size at which a male is physically capable of inseminating a mature female. Different methods for the determination of SOM in male Nephrops norvegicus are assessed and differences in the results are discussed in relation to the fishery.

Mouat, B.¹, Taylor, A¹, Atkinson, R.J.A² and Bailey, N.³

¹Division of Environmental and Evolutionary Biology, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow, Scotland, UK ²University Marine Biological Station Millport, Isle of Cumbrae, Scotland, UK ³Fisheries Research Services, Marine Laboratory Aberdeen, Scotland, UK

Structure and function of the testes of the Norway lobster, Nephrops norvegicus (Decapoda, Nephropidae)

The structure and function of the testes of the Norway lobster (Nephrops norvegicus) were assessed in mature individuals taken from the Clyde Sea Area, on the west coast of Scotland. The testes are white in colour and each consists of a convoluted collection tubule that is surrounded by many acini. These acini make up much of the wall of each collecting tubule. The acini are involved in the production of sperm, with each acinus having its own independent cycle of spermatogenesis. Spermatogonial cells can be seen on the follicular epithelium, while the centre of the acinus contains developing spermatocytes. Each acinus also contains accessory cells (also referred to as sustentacular cells). There have been no seasonal changes observed in the structure of the testes of N. norvegicus, which is consistent with previous studies that have examined seasonal changes in gonad weight. This data are very important in understanding the reproductive dynamics of a commercially important fished species.

Mugnier C.¹ and Soyez C.²

¹IFREMER, BP2059, 98846 Noumea Cedex, New Caledonia ²IFREMER, Centre Océanologique du Pacifique, BP 7004, Taravao, Tahiti

Effect of temperature decrease, hypoxia and molt stage on osmoregulatory capacity and survival in the penaeid shrimp Litopenaeus stylirostris

Shrimp farming in New-Caledonia is affected by mortalities, especially when a drop of water temperature occurs. A vibrio has been identified, but what triggers off the mortalities remains unknown. One of the hypotheses is that shrimp immunity is weakened by a cumulative effect of two or more stresses. We studied the combined effect of a decrease in temperature (between 28 C and 22 C in 24 hours) and oxygen on juvenile L. stylirostris survival and osmoregulatory capacity (OC) as a physiological indicator of stress. Mortalities started earlier at 27 C (0.6mg O₂.l^–1) than at 22 C (0.4mg O₂.l^–1), and were significantly higher for premolt and postmolt stages. Decrease of temperature had no effect on OC. OC was significantly lower in premolt stage compare to intermolt stage. Under hypoxic condition (0.6mg O₂.l^–1), CO was significantly reduced by 30% at both 27 C and 22 C for intermolt stage and 64% and 47% for premolt stage.

Munasinghe, D.H.N., Murphy, N.P. and Austin, C.M.

School of Ecology and Environment, Deakin University, Warrnambool, Australia

A preliminary analysis of the phylogenetic utility of mtDNA sequences from the 12S rRNA, COI and Cyt b gene regions in Australian freshwater crayfish of the genus Cherax.

One of the most important steps in any phylogenetic study is the choice of an appropriate gene region. For freshwater crayfish, like many crustacean groups, the majority of molecular systematic studies have utilised 16S rRNA sequences. As a consequence, this study compares the characteristics and phylogenetic utility of sequences from three other mtDNA gene regions (12S rRNA, COI and Cyt b) together with 16S rRNA sequences were obtained from a common set of 8 samples representing 4 species of freshwater crayfish of the genus Cherax from the southwest of Western Australia. The number of base pairs obtained from the regions were 537 (16S rRNA), 358 (12S rRNA), 609 (COI) and 471 (Cyto b) and are compared with respect to % of variable sites, %A-T, transition:transversion ratios, average within and between species divergence. Estimated phylogenies from the 4 regions displayed, for the most part, a high level of congruence.

Murphy, N.P. and Austin, C.M.

School of Ecology and Environment, Deakin University, Warrnambool, Australia

MtDNA 16S rRNA sequences reveal anomalies in the current classification of Australian palaemonid shrimps (Palaemonidae: Decapoda)

The systematic relationships among Australian palaemonid shrimps have been the subject of speculation for some time. A preliminary phylogenetic study was undertaken to clarify the relationships of four species, Macrobrachium intermedium, M. australiense, M. atactum and Palaemon serenus, using 16S rRNA mitochondrial sequences. Phylogenetic analyses indicated that there are inconsistencies with the current classification in two respects. Firstly, M. intermedium formed a very well supported clade with P. serenus distinct from M. australiense and M. atactum. Secondly, the latter two species, both from inland Australia, showed a high level of genetic similarity over a substantial geographic range, suggesting that they may be conspecific populations. The taxonomic implications of these findings at both the genus and species levels for Macrobrachium are discussed.

Muskó, I.B.¹ and Görög, Sz.²

¹Balaton Limnological Research Institute of the Hungarian Academy of Sciences, Tihany, Hungary ²University of Veszprém, Veszprém, Hungary

Colonization of natural substrata by the invasive immigrant amphipod Corophium curvispinum in Lake Balaton (Hungary)

Corophium curvispinum is one of the dominant invertebrates inhabiting the encrustation of the stones and other solid constructions on the shoreline, of the reed and submerged macrovegetation in Lake Balaton. This Ponto- Caspian amphipod invaded Lake Balaton in the 1930's years. We studied the colonization dynamics of different natural substrata (wood pieces and stones) placed into Lake Balaton in July 1999 by invertebrates especially by Corophium curvispinum and the relationships between the colonization dynamics and some environmental conditions in Lake Balaton. C. curvispinum and zebra mussel dominated on the substrates among 47 animal taxa and groups indentified. The density of C. curvispinum (ind. m^–2 substrate surface) gradually raised from 2400 to 83800 during the experiment (two months), depended on the nature of substrata, on water strata, on the distance from the shore and on other environmental conditions. The population structure of this amphipod also depended on the environmental conditions.

Myers, A.¹ & Lowry, J.K.²

¹Department of Zoology and Animal Ecology, Lee Maltings, Prospect Row, Cork, Ireland ²Australia Museum, Sydney, Australia

A re-evaluation of the phylogeny of the corophioidean Amphipoda

A phylogenetic hypothesis, supported by a cladistic analysis, is presented for the corophioidean Amphipoda. A new classification is proposed which includes two superfamilies, the Corophioidea and the Podoceroidea within a sub-order Corophiida. The two superfamilies represent lineages of detritivores derived by the adoption of different feeding strategies to capitalise on detritus availability in the marine environment.

Mytilineou, Ch. and Fourtouni, A.

National Centre for Marine Research, Institute of Marine Biological Resources, Ag. Kosmas, 16604, Helliniko, Athens, Greece

Size structure comparison between two Nephrops norvegicus grounds of different fishing impact

Nephrops norvegicus is a highly exploited crustacean around the word. In the present work, the impact of fishery on the size structure of Nephrops stock is examined in two areas of different fishing conditions. Data were collected during October 1993 and September 1995 by means of experimental trawl surveys in the North Evoikos Gulf, a closed basin in the east coasts of Greece. In this gulf, which is an important Nephrops fishing ground, areas closed to trawl fishery have been defined since long time. The mean sizes and the size frequency distributions of the species in two areas, one exploited and one unexploited, were compared per month during the two years of sampling using non parametric statistical tests. In almost all analyses, statistically significant differences were detected in the size structure of Nephrops between the exploited and the unexploited area, indicating the influence of trawl fishing on the species biological characteristics.

Nacorda, H.M.E.^{1, 2} and Vermaat, J.E.¹

¹Department of Environmental Resources, International Institute for Infrastructural, Hydraulic and Environmental Engineering, PO Box 3015, 2601 DA Delft, The Netherlands ²Marine Science Institute, University of the Philippines, UPPO Box 1, Diliman, Quezon City, 1101 The Philippines

Sediment remobilization and leaf harvesting by the snapper shrimp Alpheus macellarius (Chace 1988) (Alpheidae, Caridea) in a tropical seagrass meadow

Alpheus macellarius move sediments and harvest leaves in shallow Philippine seagrass meadows. To determine the contribution of these activities to seagrass dynamics, frequencies of sediment dumping and leaf clipping events were quantified from videorecords taken at half-hour intervals for 10 hours. Alpheus macellarius was only visible aboveground for 1.3 h d^–1, within which it dumped sediment 576x and clipped fresh leaf or algal fragments 46x. The estimated amount of sediment remobilized by an individual shrimp was 290 g d^–1, which translates to 1.1 kg of sediment m^–2 d^–1 for a density of 4 burrows m^–2. Its harvest biomass was 0.60 g m² d^–1, equivalent to 2.6 g m^–2 d^–1 or 49% of meadow production. Alpheus macellarius is, hence, a major herbivore of seagrass ecosystems. The gaps resulting from its bioengineering open areas for the maintenance of less competitive species, e.g., Halophila ovalis.

Negreiros-Fransozo, M.L.

NEBECC (Group of Studies on Crustacean Biology, Ecology and Culture) Departamento de Zoologia, IBB, Unesp, Botucatu (SP), Brazil

Comparative population biology of Uca thayeri (Rathbun, 1900) in six distinct subtropical mangroves from South America

Population biology of the fiddler crab U. thayeri was comparatively studied throughout a year period in the mangroves Itapanhaú, Itaguaré, Guaratuba, Comprido, Indaiá and Ubatumirim located at 23 20' to 23 35'S and 44 50' to 45 14'W. Some biotic and abiotic factors were also analyzed. Crabs were captured in low tide periods by two collectors during 15 minutes each. The studied sites are typical estuarine mangroves characterized by a soft bottom with a predominance of very fine sand. Fiddler crabs presented a striking body size difference among mangroves. All adult demographic categories of U. thayeri reach largest size at Ubatumirim followed by Comprido, being crabs from Itaguaré, Indaiá, Guaratuba and Itapanhaú smaller than the formers. Approximately 24% of the crabs from Ubatumirim are 23.3 mm of carapace width, maximum size attained by crabs from Itaguaré. This fact could be associated to a different nutritional conditions provided by the habitat, in this case it could be a high amount of organic material in the sediment.

Negreiros-Fransozo, M.L.^{1, 2}; Fransozo, A.^{1, 2}; Melo, G.A.S.³ and Bertini, G.^{1, 2}

¹NEBECC (Group of Studies on Crustacean Biology, Ecology and Culture) ²Departamento de Zoologia, IBB, UNESP, Botucatu (SP), Brasil ³Museu de Zoologia da Universidade de São Paulo, USP, São Paulo, Brasil

Assessment of brachyuran crabs diversity from non-consolidated sublittoral bottom at São Paulo northern coast, Brazil, South America

As a part of a wide survey on marine benthic invertebrate biodiversity, the brachyuran crabs from non-consolidated sublittoral bottom have been investigated at the northern littoral of São Paulo. Three distinct areas have been sampled at 5, 15, 25, 35 and 45 meters depth each by trawling with double-rig nets in all seasons of the year. Taking into account the already published faunistic lists and the data from this project, São Paulo northern coast presents 87 brachyuran species (4 Dromiidae, 1 Homolidae, 1 Tymolidae, 1 Raninidae, 12 Portunidae, 18 Xanthidae, 5 Goneplacidae, 22 Majidae, 3 Calappidae, 8 Leucosiidae, 6 Parthenopidae and 6 Pinnotheridae) as deep as 100 m. An increase in the number of occurring species can be evidenced during last 10 years. Such increment is mainly due to new occurrences of species from other Brazilian regions or even other seas like Indo-Pacific (Charybdis helleri and Scylla serrata) and Eastern Pacific (Pilumnoides perlatus and Pyromaia tuberculata). Comparing the studied area with other Brazilian regions, it can be concluded that the former have a higher biodiversity, despite of its latitude. BIOTA/FAPESP # 98/07090-3

Neil, D.M.¹, Krång, A.-S. ², Pihl Baden, S.² and Norberg, E.E.¹

¹Institute of Biomedical and Life Science, University of Glasgow, Glasgow, G12 8QQ, Scotland, UK ²Kristineberg Marine Research Station, Göteborg University, 450 34 Fiskebäckskil, Sweden

Behavioural bioassays for the exposure of Norway lobsters to manganese

Norway lobsters (Nephrops norvegicus) exposed to the elevated levels of bioavailable manganese associated with the hypoxic conditions have been found to accumulate high concentrations of manganese on their external appendages. This accumulation may serve as a useful biomarker for Mn²⁺ exposure. Since many of these appendages bear chemosensory hairs, the possibility has also been tested that this accumulation of manganese affects chemically-mediated behaviours related to feeding. The first test showed that N. norvegicus pre-exposed to manganese (6 and 11 mg Mn l^–1) for 12 days took significantly longer time to react in a flume to food stimuli than did controls, and at the higher concentration did not locate food stimuli as efficiently as the controls. In a second experiment the antennular grooming behaviour (AGB) elicited in the presence of L-glutamate disappeared in 80% of the lobsters after exposure to concentrations of 10 mg Mn l^–1 for 10 days. Thus changes in foraging behaviour and AGB may serve as useful behavioural biaossays for Mn²⁺ exposure.

Nelson, M.M.¹, Ritz, D.A.¹, Crear, B.², Ritar, A.² and Nichols, P.D.³

¹Department of Zoology, University of Tasmania, Hobart, Tasmania, Australia ²Tasmanian Aquaculture & Fisheries Institute, Marine Research Laboratories, Taroona, Tasmania, Australia ³CSIRO Marine Research, Hobart, Tasmania, Australia

Growth and lipid composition of phyllosoma of the southern rock lobster, Jasus edwardsii, fed enriched Artemia.

J. edwardsii phyllosoma were ongrown from newly-hatched to stage V. We were able to enrich Artemia with the major polyunsaturated fatty acids (PUFA) to ratios similar to that of wild caught phyllosoma. Enrichment diets included: Isochrysis galbana, oat/wheat/lecithin/oils (OWL), OWL/cholesterol, Chaetoceros muelleri/DHA-Selco, A1-Selco, Switch (OWL to DHA-Selco at stage III). Animals were counted and measured at each stage and samples taken for lipid analyses. Survival was highest from stages II-III (62-86%). Mass per individual (0.2-2.2 mg) and total length (2.1-7.1 mm) increased from stages I-V. Total lipid decreased from stages I-V (180-34 mg g^–1 dry mass), but lipid per individual increased (20^–115 µg). The major lipid class in all samples was polar lipid, followed by sterols (mainly cholesterol) and diacylglycerols. The main FA were 16:0, 18:1(n-9)c, 20:4(n-6), 20:5(n-3) and 22:6(n-3). Proper ratios of these PUFA are considered vital to survival of phyllosoma and should be considered, along with cholesterol, in diet formulation of aquacultured crustaceans.

Newman, Brent Kenneth¹ and Wooldridge, Tristram Howe²

¹Institute for Environmental and Coastal Management, University of Port Elizabeth, Port Elizabeth, South Africa ²Department of Zoology, University of Port Elizabeth, Port Elizabeth, South Africa

Influence of temperature on survival and developmental duration of mudprawn, Upogebia africana Ortmann 1898 (Decapoda: Thalassinidea: Upogebiidae), larvae reared in the laboratory

Larvae of the estuarine mudprawn, Upogebia africana, were reared in natural seawater (35 ppt) at seven constant temperatures (12, 14, 17, 20, 23, 26 and 29 C) in the laboratory. Development consists of three actively swimming stages (Zoeae 1-3) before metamorphosis to the Decapodid. The Zoea 4, despite being recorded in the natural environment, was not encountered in laboratory experiments, illustrating the ability of U. africana larvae to undergo accelerated development of the skipped stage type. A stage intermediate between the Zoea 3, Zoea 4 and the Decapodid was recorded on thirteen occasions from three different broods reared at 26 and 29 C, but this larval stage was short-lived. Completed development to the Decapodid was observed at all temperature treatments, with highest survival (all stages) recorded at 23 C. Trends in cumulative survival (all stages) could be described by quadratic regression functions. Extrapolation of the regression function for cumulative survival to the Decapodid suggests a larval thermal tolerance range of between about 9-34 C. Duration of development (all stages) was strongly influenced by temperature, ranging between about 27 days at 12 C to about 7 days at 29 C. Development rate increased with increasing temperature until plateaus were reached at 20 C for Zoea 1, and at 23 C for Zoea 2, Zoea 3 and cumulative development, beyond which temperature had no or only a limited additional effect on the rate of development. The relationship between temperature and duration of development at temperatures below where plateaus were reached is best described by a linear function for the Zoea 1, and by power functions for the Zoea 2, Zoea 3 and cumulative development. These data are discussed in relation to the mudprawns geographical distribution, and are the first investigation of this type conducted for a upogebiid prawn.

Newman, Brent Kenneth¹ and Wooldridge, Tristram Howe²

¹Institute for Environmental and Coastal Management, University of Port Elizabeth, Port Elizabeth, South Africa ²Department of Zoology, University of Port Elizabeth, Port Elizabeth, South Africa

Interaction between temperature and cyclic food availability on the mudprawn, Upogebia africana Ortmann 1898 (Decapoda: Thalassinidae: Upogebiidae), larval development in the laboratory

We exposed U. africana larvae reared in the laboratory at constant temperatures (14, 17, 20, 23 and 26 C) to cyclic periods (1 or 2 day) of food availability initiated at various times after hatching and continued throughout development. The time of initiation of a starvation/feeding cycle after hatching and the initial duration thereof were strong determinants of development rate, but had only a minimal influence on survival. As a general rule within each feeding regime (1 or 2 day cycle), development was increasingly delayed with decreasing temperature, and within a specific feeding regime increasingly delayed the later feeding commenced after hatching, even though larvae starved initially were often fed for periods well in excess of those fed immediately after hatching. U. africana are thus extremely well adapted to survive transitory periods of food limitation, far better than most decapod larvae, and are capable of completing development after feeding for less than 45% of their normal (fed) duration of development. This is undoubtedly related to facultative lecithotrophy in the Zoea 1, which is able to complete development in the complete absence of food. Energy acquired during this stage is carried over to the benefit of subsequent zoeal stages, decreasing their dependence on an external food source. We discuss these data with respect to the mudprawns adult and larval life history strategy, as well as to environmental conditions within this prawn's distribution range along the southern African coastline.

Ngoc-Ho, Nguyen

Laboratoire de Zoologie-Arthropodes, Muséum national d'Histoire naturelle, 61 rue de Buffon, 75005 Paris

A revision of the European Thalassinidea

Several major works on the taxonomy of the Thalasinidea have been published recently. Various classification systems have been proposed, viewpoints differ between authors and are even contradictory for certain species. Reexamination of materials from many museums has been necessary, a number of choices and changes have been made concerning the taxonomy of European thalassinideans. These are discussed, with particular reference to the following papers, two on the Axiidae: Sakai & de Saint Laurent (1989), Kensley (1989) and four on the Callianassidae: Manning & Felder (1991), Poore (1994), Sakai (1999), Tudge, Poore & Lemaitre (2000). Attention is also given to the differentiation of species, especially in the Upogebiidae where confusion is frequent. Distinguishing characters are presented.

Nguyen T.T.T., Meewan, M., and Austin, C.M.

School of Ecology and Environment, Deakin University, Warrnambool, Australia

Mitochondrial 16S rRNA sequences confirm the existence of two distinct genetic forms of the marron, Cherax tenuimanus (Smith)

Approximately 440 base pairs of the mitochondrial 16S rRNA gene region were sequenced from 13 Cherax tenuimanus (marron) samples from six locations and samples of two additional Cherax species from Western Australia. With the exception of the Margaret River, no variation was found within or between marron populations. In contrast marron from the Margaret River were found to be polymorphic for two highly divergent haplotypes (2.76% divergence). These findings are entirely consistent with allozyme studies that highlight the general lack of genetic variability within and between populations of this species apart from the Margaret River stocks, the translocation of marron between river systems and the occurrence of two reproductively isolated genetic forms of the marron. The taxonomic significance and implications of these findings for the conservation and management of genetic diversity within marron species are discussed.

Niamaimandi, Nassir

Persian Gulf Fisheries Research Center-Bushehr, Bushehr, Iran

Population dynamics of shrimp (P. semisulcatus) in the Persian Gulf (Bushehr waters)

The results of a trawl survey in the Persian Gulf (Bushehr waters), from 1996 to 1997 are described for shrimp (P. semisulcatus). Carapace length data were collected and growth parameters and mortality by sex estimated by ELEFAN and FISAT programs. The following estimates for males were obtained: L(infinity) = 37 mm, K = 1.8 y^–1, to = 0.3, M = 2.8, F = 4.5 and Z = 7.3. For females L(infinity) = 49 mm, K = 2.6 y^–1, to = 2.6, M = 0.2, F = 6.7 and Z = 9.9 were estimated. On the basis of these results the estimated exploitation rates for males and females are respectively 0.61 and 0.67. The value of theta is estimated at 7.8 for males and 8.3 for females. The sex ratio, males : females, is about 1.1. The spawning period was from January to March with a peak in January. Maximum age has been determined by the Caddy formula (1983) at 21 months for males and 19 months for females.

Noël, P.Y. and Anker, A.

LBIMM, Muséum National d'Histoire Naturelle & CNRS, Paris, France.

Burrowing in Caridea: observations in Processidae, Alpheidae and other families

Burrowing behaviour has been described in different groups of Crustacea; however, relatively few data is available for Caridean shrimps. Most Crangonidae bury at the surface of sediments, with the help of pleopods. Processidae "dive and swim" vertically into the (soft) sediment, digging the substrate with Mxp3 and first pereiopods, and turning the eyes forward. Several Alpheidae (mostly from the genus Alpheus) are able to produce elaborated burrows. The extension and complexity of the burrows of some goby-associated species can be compared to those of Stomatopoda or Thalassinidea. These burrows can be classified in two groups after the shape of the entrance (vertical / oblique). In all cases, burrows are excavated with the aid of the first pereiopods, sometimes used as a shovel to transport the sediment. Species inhabiting estuarine mudflats and mangrove areas produce much less elaborate burrows. Occurrence of possible burrowing behaviour in shrimps from other families is discussed.

Noël, P.Y.¹ and Pereira, G.²

¹Muséum/CNRS, Paris, France ²Instituto de Zooología Tropical, UCV. Venezuela

A phylogenetic analysis of Processidae (Crustacea, Decapoda, Caridea)

A cladistic analysis of the Processidae was performed, based on morphological characters. Outgroups were selected within Hippolytidae, Alpheidae and Pandalidae; the latter was used to root the tree generated using the program PAUP. The entire data set consisted of a data matrix of 33 taxa by 64 characters (unordered). Results show a single tree of 394 steps and CI of .317 . Representatives of all genera were included. The Processidae remain as a monophyletic group defined by 11 synapomorphies (.75 boostrap). The sister group of the Processidae seems to be the Hippolytidae. Within the Processidae, the genus Ambidexter is very well supported with 6 synapomorphies; also the genus Clytomanningus holds as monophyletic. The genera Nikoides and Processa are paraphyletic, however some species groups are well defined. Finally, our analysis suggest that the genus Clytomanningus and Hayashidonus include the most primitive species of the family.

Nunomura, Noboru

Toyama Science Museum, Japan

Seashore isopod crustaceans from Central Japan

The taxonomic study on the shore isopod crustaceans has been much neglected in Japan, even in the central Honshu near Tokyo. Therefore, I tried to make a series of taxonomic studies on the materials obtained from the seashores of the said districts in 1997-1998. As the results, 60 species were confirmed from Boso Peninsula, Izu Peninsula, Izu Islands (these 3 areas are Pacific sides), and Noto Peninsula (the Sea of Japan side). The cluster analysis of these 4 areas show that the Izu Islands is most strongly different from the other three areas. Though Noto and Boso are most closely allied, the dominant species of each area is quite different. In addition some biologically noteworthy species were found: Through these studies, nine species were already described as new to science from Izu Islands, and 2 species of Anthuridea and a species of arcturid Valvifera from Izu Peninsula were proved to be undescribed.

Nyssen F.^{1, 2}, Graeve M.³, Brey T.³, Lepoint G.¹, Dauby P.^{1, 2} and De Broyer C.²

¹Laboratory of Oceanology, University of Liège, Sart Tilman B6, B-4000 Liège, Belgium ²Royal Belgian Institute of Natural Sciences (RBINS), 29 rue Vautier, B-1000 Brussels, Belgium ³Alfred-Wegener-Institut für Polar- und Meeresforschung, Columbusstrasse, D-27568, Bremerhaven, Germany

Use of stable isotopes and fatty acids to delineate amphipods trophic status in the High Antarctic

In the light of the importance of peracarid crustaceans and Amphipoda in particular in Antartic ecosystems, the characterization of their trophic roles could contribute to a more accurate picture of the trophic structure and fluxes in Antarctic benthic communities. Stable isotope ratios (carbon and nitrogen) and fatty acids were used as tracers of diets to delineate the trophic relationships involving amphipods in Antarctic food webs. These techniques provide signatures based on actual food assimilation and are integrated over a period corresponding to the turnover time of the analysed tissues These still preliminary results correspond rather accurately to the trophic classification based on gut content previously described. Since the fundamental difference between both approaches is the time scale, this coincidence could indicate that there are no distinct changes in feeding strategies over time for the considered species.

Nyssen F.^{1, 3}, Scailteur Y.³, Dauby P.^{1, 3} and De Broyer C.³

¹Laboratory of Oceanology, University of Liège, Sart Tilman B6, B-4000 Liège, Belgium ²Royal Belgian Institute of Natural Sciences (RBINS), 29 rue Vautier, B-1000 Brussels, Belgium

Gut contents and functional morphology of mouthparts as a tool to characterize Antarctic amphipod feeding patterns

In many areas of the Southern Ocean coastal and shelf ecosystems, the peracarid crustaceans, especially the Amphipoda, are among the most speciose and diverse taxa of the zoobenthos. This work is in line with a multidisciplinary study of amphipods ecological role in Antarctic benthic systems, and is aiming to accurate our limited knowledge concerning amphipod trophic patterns. The selection of the species according to their supposed feeding habits has been achieved so that to cover a quite wide range of trophic types (from suspension-feeders to scavengers). The study of the functional morphology of amphipod feeding appendages has been combined to gut contents analyses in an attempt to correlate mouthparts structure and feeding strategies and in a second time to give answers to the question of trophic niche fragmentation.

O'Brien, J.J.

Department of Biological Sciences, University of South Alabama, Mobile, Alabama, USA

Defenses of brachyuran crabs against parasitization by castrating barnacles

The gonads of crabs infected by kentrogonid barnacles (Thoracica: Rhizocephala) never mature. This implies there will be strong selective pressure for mechanisms that lower infection success of the parasites. Larvae of many rhizocephalan species do not survive well at low salinities, thus freshwater regions of bays may serve as refuges. Potential hosts have been observed to remove the infective stage of the parasite through the activities of gill cleaners and/or walking legs. Intermolt crabs appear to be more refractory than vulnerable postmolt individuals. There may also be a refuge in size, for many rhizocephalan species in the Sacculinidae do not infect large hosts although other mechanisms also influence size-prevalence distribution. In the laboratory, parasite larvae will settle and metamorphose on species of crabs that are not parasitized in the wild suggesting that there are effective post-infection defenses as well.

O'Hara, Timothy D.

Museum Victoria, GPO Box 666E, Melbourne, Vic. 3001, Australia

Quantitative biogeography in the Southern Ocean: deriving processes from pattern

Modern multivariate statistics and genetic data have allowed biogeography to progress from its speculative origins into the realm of science. Three case studies are presented that explore various biogeographical patterns and processes in Southern Australia and the Southern Ocean. The first case study examines the pattern of distributions of benthic species and communities throughout Bass Strait in SE Australia and relates these patterns to the major environmental factors operating in the region. The second case study examines the distribution and origin of decapods and echinoderms along the entire Southern Australian coastline. Patterns of endemicity, species-richness and turnover are described, the origin of the fauna is examined, and preliminary genetic data is used to test the hypothesis that the closure of Bass Strait during Pleistocene glaciations has led to allopatric speciation. The third case study explores the origin of the fauna of Macquarie Island, located in the Southern Ocean mid-way between Australia and Antarctica. Macquarie Island has only recently emerged (<600 kya) and the mode of dispersal to the island can be deduced from the distribution, habitat and life history characteristics of each species. Decapods are an ideal source of biogeographical data as their taxonomy is relatively well-known and stable, they form a significant component of the benthic fauna at most depths, and they are amenable to further genetic and biological study.

Oh, C.-W.¹ and Ma, C.-W.²

¹Department of Marine Resources, Mokpo National University, Chonnam 534-729, Korea ²Biological Sciences, Soonchunhyang University, Chungnam 336-600, Korea

Growth and reproductive biology of the freshwater shrimp Exopalaemon modestus in Korea

The growth and reproductive biology of the freshwater shrimp Exopalaemon modestus (Heller, 1862) were studied in Young-am Lake, Korea, between January and December 1999. Size of female maturity was determined from the proportions of ovigerous females. The size at which 50% of females are mature is estimated (95% confidence interval) as 11.55 mm 1.95 mm carapace length. Brood size was isometric functions of female body size. Based on dry weight, the reproductive output (RO) averaged 17.44. Ovigerous females occurred in May-September. The main spawning season (percentage ovigerous > 50%) from May-June, was reflected by higher gonad index. The ovarian weight between females with non-eyed egg and eyed egg stage was significantly different. This indicates that ovarian maturation occurs during the incubation time, suggesting that females were potentially consecutive breeder, capable of multiple spawning during a spawning season. Length-frequency distribution showed that the population had two modal size groups per year, displaying similar pattern in both males and females. Parameters of growth were estimated using the von Bertalanffy growth function (VBGF). Females grew faster and reached a larger size at age than males (K = 0.58 y^–1and L = 21.39 mm CL for females, and K = 0.62 y^–1and L = 18.40 mm CL for females). Longevity was estimated to be 1.11.3 y.

Ohji, Madoka¹, Takeuchi, Ichiro², Tanabe, Shinsuke³ and Miyazaki, Nobuyuki¹

¹Otsuchi Marine Research Center, Ocean Research Institute, The University of Tokyo, Iwate, Japan ²Department of Life Environment Conservation, Faculty of Agriculture, Ehime University, Matsuyama, Japan ³Center for Marine Environmental Studies, Ehime University, Matsuyama, Japan

Embryonic exposure of Caprella danilevskii (Amphipoda: Caprellidea) to tributyltin (TBT)

Embryos of Caprella danilevskii (Amphipoda: Caprellidea) were exposed to 5 concentrations from 0 to 10,000 ng TBTCl/L, and hatched juveniles were reared in the uncontaminated seawater more than 1 generation. Even at lowest doze, 10 ng TBTCl/L, the survival rate reduced less than 50% when juveniles matured. In the 1st generation, percentage of female increased more than 80% at dose of 100 and 1,000 ng TBTCl/L. The high decrease of survival rates at low doze of 10 ng TBTCl/L and change of sex ratio lead that residue of low TBT may result in continuous disturbance of distributions of Caprella. Shortage for the experiments less than 2 months and clear difference of survival rate indicate that Caprella is a suitable protocol for assessing the endocrine disruptor effect by the anthropological chemicals in the marine ecosystem.

Olesen, J.

Zoological Museum, University of Copenhagen, Denmark

Larval development and embryology of the Branchiopoda in a phylogenetic context

Information from larval development of the Branchiopoda has only rarely been put into a phylogenetic framework. I will review the larval development or embryology of various major Recent branchiopod taxa, like the Anostraca, Conchostraca, Cladocera and various fossil branchiopod taxa like Lepidocaris and Rehbachiella. Much new information will be included for the recent taxa. It will be evaluated to which extent larval and embryonic information can help resolving the phylogeny of the Branchiopoda. One important aspect is the monoplyly of the Branchiopoda. A number of supporting characters for the Branchiopoda - relating to larval development or ontogeny - can be identified. Among these are similar arrangements of the early trunk limb buds as elongate subdivided buds. The naupliar feeding apparatus of a number of those taxa that have free-living larvae (Anostraca, Notostraca and 'Conchostraca') are also very similar and includes a pair of long, natatory second antennae each with a pair of very long setose endites which are involved in food manipulation, and a very similar three-segmented uniramous manibular palp. These characters are not present in the fossil branchiopod-like Rehbachiella and would place this taxon outside a core group of Branchiopoda. Another important aspect is the occurrence of free-living larvae versus direct development within the Branchiopoda. All 'larger branchiopods' (Anostraca, Notostraca and 'Conchostraca') have, with one exception (Cyclestheria), free-living larvae, while cladocerans, with one exception (Leptodora) have direct development. The occurrence of these different development styles will be discussed in a phylogenetic context.

Olesen, J.¹ and Grygier, M.J.²

¹Zoological Museum, University of Copenhagen, Denmark. ²Lake Biwa Museum, Shiga, Japan

Comparative larval development of conchostracan families from Japan

No SEM photographs of non-brooded clam shrimp nauplii have yet been published, only those of the brooded (embryonic) nauplius of Cyclestheria hislopi. We present the early results of an SEM study of the larvae of several Japanese conchostracans, three spinicaudatans - Caenestheriella gifuensis (Ishikawa, 1895), Leptestheria kawachiensis Uéno, 1927, Eulimnadia braueriana Ishikawa, 1895 - and one laevicaudatan - Lynceus biformis (Ishikawa, 1895). The study includes thereby all accepted conchostracan families, except Cyclestheriidae. The larvae were captured in puddles formed in ruts in rice fields in Kusatsu city, Shiga Prefecture, at various times of the year after rains and sometimes briefly reared in the laboratory after collection, or they were reared from dried rice paddy mud from various places in southern Shiga Prefecture. Larvae were preserved in 5% formalin. Many features related to the naupliar feeding apparatus are strikingly similar in the four examined species, such as the arrangement of the very long antennal endites and the three-segmented, uniramous mandibular palp. In other respects there are many differences between the examined species, e.g., with respect to the development of the carapace or the shape of the labrum, the latter appearing to be taxon specific. The study aims at providing complete descriptions of all included species and discussing the information in a phylogenetic context.

Oliveira, D.F.¹ and Cobo, V.J.^{1, 2}

¹Department of Biology, University of Taubaté - UNITAU, São Paulo, Brazil ²NEBECC - Group of Studies on Crustacean Biology, Ecology and Culture

Feeding behavior of the Stenorhynchus seticornis (Majidae, Inachinae), from Southern Brazilian Coast

The organisms ability to obtain food on the environment is a basic requirement for survival, and a limiting factor to species distribution. The goal of this study was identify the S. seticornis food items, between juveniles and adult and between sex. Monthly collections were carried out from January to December 1999 and was used the Frequency of Occurrence method. Unicellular algae was the main food item recorded, with peaks in January and February (92.8% and 97.1% respectively) and the sediment was founded with frequencies above of 60% in all stomachs of all interest groups. This can suggest that S. seticornis uses the deposit feeding as the main mechanism for food acquisition.

Oliveira, G.T.¹, Fernandes, F.A.^{1, 4,} Bond-Buckup, G.^{2, 4}, Bueno, A. A.^{2, 4} and Silva, R.S.M.^{3, 4}

¹Faculdade de Biociências; Departamento de Ciências Fisiológicas, PUCRS, BR ²Departamento de Zoologia e PPG Biologia Animal, UFRGS, BR ³Departamento de Fisiologia, UFRGS, BR ⁴CNPq

Circadian and Seasonal Variation in the Carbohydrate Metabolism of Aegla platensis (Decapoda, Anomura, Aeglidae)

Aegla platensis specimens were sampled monthly from August/99 to August/00, in Taquara, RS, Brazil. Haemolymph samples of both sexes were collected in the field at 6 a.m., 6 p.m. and 12 p.m.. Glycogen was extracted following Van Handel (1965), and quantified by the glucose oxidase method after acid hydrolysis and neutralization. Haemolymphatic glucose levels were measured by the glucose oxidase method (Kit labtest). Test results showed significant differences on the levels of haemolymphatic glucose and tissue glycogen for both sexes. One-way analysis of variance presented both circadian and seasonal variation in female levels of haemolymphatic glucose. Significant differences in glycogen concentration in tissues were observed in relation to the seasons of the year, for both males and females (p<0,05), but not to the different times of the day.These data indicate high levels of haemolymphatic glucose, and variation in tissue glycogen concentration are related to the reproductive period of the species.

Oliveira; G.T.¹, Fernandes, F.A.^{1, 4}, Bond-Buckup, G.^{2, 4}, Bueno, A. A.^{2, 4} and Silva, R.S.M.^{3, 4}

¹Faculdade de Biociências; Departamento de Ciências Fisiológicas, PUCRS, Brazil ²Departamento de Zoologia e PPG Biologia Animal, UFRGS, Brazil ³Departamento de Fisiologia, UFRGS, Brfazil ⁴CNPq, Brazil

Circadian and Seasonal Variation in the Carbohydrate Metabolism of Aegla ligulata (Decapoda, Anomura, Aeglidae)

Samples of the A. ligulata were collected monthly from August/99 to August/00 in Tainhas, RS, Brazil, at 6 a.m., 6 p.m and 12 p.m. Samples of haemolymph of both sexes were collected in the field with a syringe containing potassium oxalate (10%) as anti-clotting. In the laboratory, samples of the different tissues (hepatopancreas, gills and muscle) were taken to determine glycogen levels (g%). Glycogen was extracted following Van Handel (1965), and quantified by the glucose oxidase method. Haemolymphatic glucose levels were measured by the glucose oxidase method (Kit labtest) and the results expressed in mg/dl. The data indicate the presence of high levels of haemolymphatic glucose, specially in springtime; there are also circadian differences between male and female. These variations seem to be related to the reproductive period of the species, food availability and/or environmental exploration degree. These factors lead to different metabolic adjustments in distinct species of crustaceans.

Østergaard, Pia

Zoology, The Natural History Museum, Cromwell Road, London SW7 5BD, UK

"Dwarf" male characterization in Chondracanthidae (Copepoda)

Members of the copepod family Chondracanthidae have "dwarf" males, which live attached to large females. These males have long been referred to as "parasitic" on the females but nutritional dependence has never been demonstrated. Key unanswered questions include: What is the impact of small size on male anatomy in Chondracanthidae? Are there any special "dwarf" male characters? Or is it simply being a parasite that has had an impact on the male anatomy? Detailed microscopy studies (both light and electron microscopy) of male morphology and anatomy are presented to help elucidate these questions.

Østergaard, Pia

Zoology, The Natural History Museum, Cromwell Road, London SW7 5BD, UK

Evolution within the Chondracanthidae (Copepoda)

The Chondracanthidae is a family of highly modified copepods parasitic on marine demersal fish. The family displays great sexual size dimorphism with a large and modified adult female usually carrying a small, less modified male attached to her genital area. At present two subfamilies are recognised comprising a total of 43 genera and approximately 150 species. The classification within the family is unstable as the generic diagnosis were based on female characters only, and undue weight was attributed to shape of the body and the number, shape and distribution of body processes. A phylogenetic analysis using PAUP was performed using 238 male and female characters. The analysis shows different resulting trees when male and female characters are partitioned or combined. The use of male and female characters in the classification of Chondracanthidae will be discussed as well as the validity of the current two subfamilies.

Papadopoulos, I.¹, Wooldridge, T.H.¹ and Newman, B.K.²

¹Department of Zoology, University of Port Elizabeth, Port Elizabeth, South Africa ²Institute for Environmental and Coastal Management, University of Port Elizabeth, Port Elizabeth, South Africa

The effect of temperature and salinity on the larval development of Hymenosoma orbiculare reared in laboratory, and its implications for estuarine management

Available data suggest that the crown crab, Hymenosoma orbiculare, follows a different life-history strategy compared to most southern African estuarine decapods, completing its entire life cycle within estuaries. We examined, in the laboratory, the influence of salinity and temperature on the larval development of H. orbiculare, with the objective of determining the salinity tolerance range and preference of the larvae and thereby providing data on which management decisions can be based. Larvae were reared individually in factorial combinations of temperature and salinity (12, 16, 20, 24, 28 and 32 C and 0, 7, 14, 21, 28, 42 and 49 ppt). At all temperatures larvae at 0 and 7 ppt died within a few hours of transfer to these salinities, and no larvae were able to complete development to the first crab at 28 and 32 C. Temperature effects were expressed predominantly through modification of development rate, whilst the main effect of salinity was on survival. Within the apparent preferred temperature range (16 - 24 C) development, as determined by survival, was optimal at 28 ppt. H. orbiculare larvae are therefore well adapted to tolerate salinities typical of large reaches of estuaries, but the tolerance range was somewhat narrower than expected considering that this crab is also recorded in relict estuarine lakes (freshwater). We discuss these data and their implications for estuarine management.

Park, C.J.¹, Koo, H.², Hwang, U.W.³, Whang, I.J.¹ and Kim W.¹

¹School of Biological Sciences, Seoul National University, Seoul, Korea ²Department of Biological Science, Sangji University, Wonju, Korea ³School of Science Education, Teacher's College, Kyungpook National University, Taegu, Korea

The ribosomal DNA intergenic spacer of a tongue worm, Sebekia mississippiensis (Pentastomida: Porocephalida)

Length heterogeneity of the rDNA IGS in a tongue worm, Sebekia mississippiensis was detected by long PCR method. Four IGS types (SI-I, SI-II, SI-III, SI-IV) were identified and completely sequenced. Each length of four IGS types is 4772bp, 3960bp, 3554bp, and 3350bp, respectively and all types contain two nonrepetitive regions blocked by one long repetitive region which consists of 203bp-A subrepeats and 155bp-AT subrepeat. Length heterogeneity of S. mississippiensis IGS is dueto the different copy number of 203bp-A subrepeat in repetitive region. Such length heterogeneity with the difference of copy number may be caused by misalignments between subrepeats which may occur during the process of unequal crossing over, a major mechanism of concerted evolution. The putative gene promoter of rDNA was identified in nonrepetitive region II which is located upstream from 5' end of 18S rDNA coding region and was very similar to the gene promoter sequences of other crustaceans.

Pastorinho, R.¹, Morgado, F.¹, Fonseca, J.C.², Marques, J.C.² and Azeiteiro, U.M.M.²

¹Departamento de Biologia, Universidade de Aveiro, Aveiro, Portugal ²IMAR - Institute of Marine Research, c/o Department of Zoology, Faculty of Sciences and Technology, University of Coimbra, 3004-517 Coimbra, Portugal

Morphometry, production, biochemistry and histochemistry of the suprabenthic mysid Mesopodopsis slabberi Van Beneden (Crustacea:Mysidacea) in the Mondego estuary (Western Coast of Portugal)

The morphometry, production, biochemistry and histochemistry of the mysid Mesopodopsis slabberi van Beneden are described from a warm-temperate estuary in the Western Coast of Portugal. Mysids were sampled using zooplankton and suprabenthic nets, with 335m and 500m mesh size respectively, from June 1999 to July 2000. Morphometric relationships in M. slabberi were determined from freshly caught specimens. Significant positive correlations between total length (TL) and cephalic length (CL) (TL = 2.5 CL + 0.012) and between dry weight (DW) and total length (LnDW = 3.0298 LnTL - 6.0229) were found. All size classes, from 0.95 to 11.36 mm, were equally represented throughout the year. Moreover, juveniles, immature females, mature ovigerous females carrying eggs or embryos, and mature resting females were always found during the sampling period. As a whole, this pattern suggests that reproduction is continuous rather than seasonal, which together with migrations made identification and tracking of any population groups impossible from the analysis of size-frequency diagrams. The annual production was 13,17 mg.m-3 y^–1, and the annual P/B ratio was 9,32. This species abundance and turnover rate strengthen the hypothesis that it plays an important role in the Mondego estuary food web. Statistical analysis (ANOVA) revealed significant seasonal differences in biochemical composition, and also between juveniles, females, and males. Environmental conditions (trophic conditions) and reproduction appeared to be the main processes influencing the seasonal patterns of variation in the biochemical composition.

Peart, R.A.

Division of Invertebrate Zoology, Australian Museum, 6 College St, Sydney, NSW, 2010, Australia

The systematics and biogeography of ampithoid amphipods (Crustacea) from Australian waters

Ampithoids are algal-dwelling corophioid amphipods. They inhabit shallow water, living mainly in brown algae (Phaeophtya) communities. Ampithoids are abundant, relatively large and strongly coloured amphipods. There about 120 known species of ampithoids throughout the world. Only thirteen of these species are known from Australian waters (Haswell, 1879; Sheard, 1936; Freewater and Lowry, 1994; Poore and Lowry, 1997; Just, 2000). The current study describes 60 species, 85% of which are new to science. These species of ampithoids occur in seven genera. A preliminary phylogenetic analysis of all ampithoid taxa is presented. Based on these results the relationships of the Australian ampithoid fauna to the Indo-Pacific and other faunas is discussed.

Pereira, V.F.G.C.¹, Veloso, V.G.² and Cardoso, S.R.²

¹Centro de Ciências Exatas e da Natureza - Depto. Ciências Biológicas - Universidade Severino Sombra (USS). Praça Martinho Nóbrega, Centro, Vassouras, RJ. Cep 277000-000.Brazil ²Laboratório de Dinâmica de Populações Marinhas - Depto. Ciências Naturais - Universidade do Rio de Janeiro (UNI-RIO). Av. Pasteur nº296 - Urca - Rio de Janeiro, RJ. CEP 22290-240. Brazil

Secondary production of Sphaeroma serratum ( Isopoda : Flabellifera) of the Marina da Glória in Rio de Janeiro City, RJ, Brazil

Sphaeroma serratum is a non-native isopod, found in abundance in the rocky coast of the Marina da Gloria, in Rio de Janeiro City, RJ, Brazil. The objective of this study is to obtain data relating to secondary production and to production : biomass; this is a parameters being studied for the first time in relation to this species. Monthly collections were made from September/97 to August/98, using two transects perpendiculars to the water line, divideds in four stratas with three replics each, using a 0,001575 m² demonstrator. Each individual crustacean was counted and checked for sex, measured and grouped in 1mm classes and, later, cremates. The production was estimated by the weight specific growth rate method. Production was 61,27 mgAFDWm^–2y^–1, for males and, 27,76 mgAFDWm^–2y^–1, for females. The biomass, 8,71 mgAFDWm^–2 for males, and 6,09 mgAFDWm^–2 for females. The P/B was found to be 7,03 y^–1 and 4,56 y^–1 for males and females, respectively.

Pérez-Losada, M.¹, Jara, C.G.², Bond-Buckup, G.³, Porter, M.L.¹ and Crandall, K.A.¹

¹Department of Zoology, Brigham Young University, Provo, UT, 84602-5255 USA ²Instituto de Zoología, Casilla 567, Universidad Austral de Chile, Valdivia, Chile ³Departamento de Zoologia, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, Brasil

Anomuran phylogenetic relationships: on the taxonomic positioning of Aeglidae freshwater crabs (Crustacea, Anomura)

Taxonomic positioning of the Aeglidae freshwater crabs and phylogenetic relationships among Anomura higher level taxonomic groups need to be clarified. We sequenced approximately 2,000 nucleotides of the ribosomal 18S gene to test previous morphological hypotheses concerning family and superfamily relationships. Twelve new sequences from the superfamilies Galatheoidea, Paguroidea, Hippoidea (Anomura) and Callinassoidea (Thalassinidea) were included. These were combined with previously published sequences from GenBank. Our results show the clear separation of Aeglidae from the other Galatheoidea families, which form a sister group with Paguroidea. Within the Galatheoidea, chirostylids and porcellanids also form a sister group. Hippoidea was revealed as the most basal group within the anomurans.

Poltermann, M.

Norwegian Polar Institute, Polar Environmental Centre, 9296 Tromsø, Norway

Gammarus wilkitzkii and Gammarus setosus - a permanent and a temporary inhabitant of Arctic sea ice

Two taxonomically closely related amphipod species Gammarus wilkitzkii and G. setosus inhabit the underside of Arctic sea ice. G. wilkitzkii lives permanently at the underside of drifting pack ice in the Arctic Ocean, whereas G. setosus only temporarily inhabits the fast ice of high Arctic fjords (Svalbard). Population dynamics, growth performance, productivity, reproduction biology, feeding ecology and behavioural aspects of these two species are compared to discuss why only G. wilkitzkii is able to colonise Arctic sea ice permanently.

Poore, Gary C. B.¹ and Brandt, Angelika²

¹Museum of Victoria, GPO Box 666E, Melbourne, Vic. 3001, Australia ²Zoological Institute and Zoological Museum, Martin Luther-King-Platz 3, 20146 Hamburg, Germany

The "Flabellifera" revisited: a phylogenetic analysis of some suborders of isopods (Malacostraca)

Recent phylogenetic analyses of the Isopoda have been not well resolved, e.g. Waegele (1989) and Brusca & Wilson (1991). Characters from the literature and specimens representing all families and many genera in the collections of Museum Victoria, the Zoological Museum in Hamburg, plus type material from other museums were reappraised. A data matrix of 159 characters was established for 40 taxa of generic, family or higher level. A phylogenetic analyses ( PAUP* 4.0) revealed three clades, none fully resolved. The first comprising Cirolanidae, Cymothoidae and similar families incorporated the suborders Gnathidea, Epicaridea and Anthuridea and was largely defined on the basis of mandibular structure. It includes scavenging, predatory and parasitic taxa. The second, sister taxon of the first, included Limnoriidae, Keuphyliidae and Hadromastacidae. The third included the suborder Valvifera, sister taxon to Sphaeromatidae and its offshoots, Serolidae and Bathynataliidae, Plakarthriidae, the fossil Schweglerella, and Paravireia. This last group share a well defined pleopodal branchial cavity and differentiated pleopods.

Porter, M.L., Perez-Losada, M. and Crandall, K.A.

Department of Zoology, Brigham Young University, 574 Widtsoe Bldg., Provo, Utah, USA

Relationships within the Decapoda: The Reptantian Riddle

Previous studies of Reptantian systematics have been unable to elucidate relationships within the group due to a lack of useful markers. Therefore phylogenetic relationships among the Reptantian infraorders (Caridea, Stenopodidea, Palinura, Astacidea, Thalassinidea, Anomura, and Brachyura) were inferred using 18S and 28S ribosomal DNA. Molecular data were obtained from Genbank and from unpublished sequences. Phylogenetic trees were generated by parsimony and maximum likelihood analyses, using bootstrap replicates as an indication of nodal support. The Astacidea (Astacoidea, Parastacoidea, and Nephropoidea) were supported as a monophyletic group, with Palinura as the sister group. Although bootstrap values were low, the anomurans and brachyurans were placed basally to the rest of the Reptantia for both genes. Further studies include the search for nuclear coding genes that contain more phylogenetic signal for this group.

Prerost, J.E.

Dept. of Marine Sciences, University of South Alabama, Mobile, AL 36688-0002, USA; Dauphin Island Sea Lab, 101 Bienville Blvd., Dauphin Island, AL 36528, USA

Top down control of Squilla empusa population size and structure by Lutjanus campechanus, red snapper, in the north central Gulf of Mexico

Squilla empusa, a mantis shrimp, is found burrowed in muddy sediments throughout the north central Gulf of Mexico. An important portion of the diet of red snapper, Lutjanus campechanus, is composed of both the benthic adult and pelagic larval stages of mantis shrimp. The length and sexual composition of adult mantis shrimp collected by trawl and from stomach contents of red snapper have been compared to determine the impact of red snapper on the size and sexual structure of Squilla empusa populations. The data collected will be used in conjunction with behavioral experiments in order to examine the role of behavior and burrows in the predation on mantis shrimp by red snapper.

Queiroga, H.

Departmento de Biologia, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal

Relation between wind stress and input of Carcinus maenas megalopae to the Ria de Aveiro (northwestern Portugal)

Megalopae of Carcinus maenas were sampled in the Ria de Aveiro, during spring and summer of 1991. At weekly intervals, plankton samples were collected bellow the surface, at mid-water and above the bottom during night and day flood tides, with the use of plankton nets. In order to evaluate the relationship of wind speed and direction and input of megalopae to the estuary, a complex correlation coefficient between megalopae concentration and average daily wind stress was calculated. Maximum values of the correlation coefficient were obtained when concentration of megalopae was lagged after wind stress by 3 d. The geographic direction of the correlation was 2º, meaning that input of megalopae to the estuary increased as southward wind stress decreased. No high densities of megalopae were found associated with strong southward wind stress. The results are consistent with an onshore transport of megalopae over the shelf following relaxation of southward, upwelling favourable, wind events.

Raethke, N.¹, MacDiarmid, A.² and Montgomery, J.³

¹School of Biological Sciences, University of Auckland and National Institute of Water and Atmospheric Research, P.O. Box 14901, Kilbirnie, Wellington, New Zealand ²National Institute of Water and Atmospheric Research, P.O. Box 14901, Kilbirnie, Wellington, New Zealand ³School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand

Chemosensory communication in rock lobsters (Jasus spp.) (Decapoda, Palinuridae)

Chemical signals play an important role in the social life of many crustaceans, but most of the research has been investigated on Brachyura and Macrura which tend to be aggressive and asocial for most of their lives coming into close contact only to mate. There has been very little research on chemical communication of spiny lobsters which unlike crabs and clawed lobsters are highly gregarious for much of their lives. However, it is assumed that similar mechanisms operate in Palinuridae as in other decapods. It has been suggested that the odour of these animals plays a role in cohabitation of juveniles as well as of adults, but it is yet not specified whether this odour is based on the pheromone-containing urine. Experiments will clarify the role of pheromones a) in shelter occupation throughout the year and b) in the complex mating behaviour during the short reproductive periods.

Rainbow, P.S.

Department of Zoology, The Natural History Museum, London SW7 5BD, UK

Ecophysiology and trace metal uptake in crabs and other crustaceans

Uptake of dissolved trace metals by crustaceans can be affected by the physicochemistry of the dissolved metal, and by physiological change by the crustacean. Physicochemistry controls the speciation of the dissolved metal, including the activity of the free metal ion and its complexation by organic or inorganic chelating agents, especially chloride. Different routes are potentially available for metal uptake; a neutral complex may diffuse across the membrane, and the free metal ion may be transported via a protein career. While physicochemistry controls the chemical nature of the dissolved metal, physiology affects the activities of the different uptake routes available. For example, metal uptake rates may change in a euryhaline crab adapting physiologically to reduced salinity. Examples are given of crustaceans responding physiologically to environmental changes, thereby gaining some control of metal uptake otherwise determined by physicochemistry. Such physiological intercession may, however, be as rare as the crustaceans concerned are common.

Rainbow, P. S.¹ and Wang, W.-X.²

¹Department of Zoology, The Natural History Museum, London SW7 5BD, UK ²Department of Biology, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong

Trace metal assimilation by barnacles from the diet, a neglected route of uptake

Assimilation of trace metals from the diet is a key factor in their substantial accumulation by barnacles. Assimilation efficiencies (AE) of Cd, Cr, Se and Zn by Balanus trigonus and Elminius modestus have been measured from diets of zooplankton and phytoplankton including diatoms, a dinoflagellate, a prasinophyte and a chlorophyte. AEs of Cd, Se and Zn varied greatly with phytoplankton type ingested, and for Cd, Se and (variably) Zn the AE was correlated with the percentage of metal in the cytoplasm of the phytoplankton. AE was generally higher from the zooplankton diet than from phytoplankton. Variation in AEs of Cd, Se and Zn could not be explained by any correlation with the percentage of copepod metal burden held in the soft tissues. Modelling of the accumulation of Cd and Zn by Elminius modestus predicts that for each metal >97% of accumulated metal is derived from dietary ingestion.

Reed, Sadie K., Coelho, Vânia R. and Brusca, Richard C.

Columbia University, Biosphere 2 Center, P.O. Box 68, Oracle, AZ 85623, USA

Eye pigmentation loss in two species of gammaridean amphipods, Ceradocus rubromaculatus and Leucothoe spinicarpa

A degenerative eye condition, manifested in pigmentation loss, has been investigated and described in two species of amphipods, Ceradocus rubromaculatus (Stimpson, 1855) and Leucothoe spinicarpa (Abildgaard, 1789). The specimens were collected monthly from an enclosed marine environment (Biosphere 2 Center's 2.500.000 liter coral reef biome) between July 1999 and June 2000. The amphipod eyes were evaluated and classified according to degrees of pigmentation loss: up to 10%, between 10 and 50% and more than 50%. The different levels appear to be successive events of the same abnormality. Additionally, large amounts of a white granular substance have been observed around the ommatidial facets of live specimens. Yet, it is unclear if these conditions are related. Although museum collections of these species from natural environments showed similar degrees of pigmentation loss, there is little information on this phenomenon in the amphipod literature. In C. rubromaculatus, the frequency of eyes with normal pigmentation alternates periodically with the frequency of pigmentation loss. In contrast, in L. spinicarpa the frequency of pigmentation loss is always high. The distribution of the various levels of pigmentation in the population apparently depend on body size (age) in both species.

Relini, M.¹, Maiorano, P.², D'Onghia G.², Orsi Relini L.¹ and Tursi A.²

¹Department of Territory and Resources, University of Genova, Via Balbi, 5 - 16126 Genova, Italy ²Department of Zoology, University of Bari, Via Orabona, 4 - 70125 Bari, Italy

Tagging of the deep-sea shrimp Aristeus antennatus (Risso, 1816) in the Mediterranean Sea

The blue and red shrimp, Aristeus antennatus (Risso, 1816), which is generally fished by trawling at depths between 300 and 700 m, is one of the most important demersal resources in the Mediterranean. A remarkable quantity of work has been devoted to describe its fishery and biology. However, some basic aspects remain obscure, such as the age of exploited shrimps and the displacement of this species during its lifespan. A simple method to tag and release A. antennatus was tested in order to obtain direct information on the displacement and growth. This is probably the first case of tagging a bathyal crustacean decapod of the group of Natantia. A total of 841 shrimps was tagged and released; 23 specimens were recaptured, most of them shortly after release. Two of them, recaptured 1 and 9 months after, gave interesting indications about the displacement of the shrimps both in vertical and horizontal space and about growth rate.

Richardson, Alastair, M.M.

School of Zoology, University of Tasmania, Hobart, Australia

Burrows on land: freshwater crayfish

All freshwater crayfish make burrows to a greater or lesser extent, some entirely within standing water, others at its margins, and still others on land well away from surface water. The most terrestrial crayfish construct burrows that do not even contact the water table. This contribution discusses the form and function of freshwater crayfish burrows, particularly those found away from standing water, drawing largely on studies of the parastacids. Burrow form varies between species, but is constrained by soil depth and vegetation. The burrow may provide shelter from physical conditions or predators, food or a place to mate and rear young. Burrow form and function are interrelated; examples of burrow structures that control water conditions, that are related to food supply and that are related to offspring care are described. Although their contribution to soil turnover may not always be large, crayfish burrows are a good example of ecosystem engineering.

Richter, S.

Comparative Zoology, Institute for Biology, Humboldt-University Berlin, Philippstr. 13, 10115 Berlin, Germany

Phylogenetic relationships of lophogastrid genera and the position of the Lophogastrida within the Peracarida (Malacostraca)

The Lophogastrida comprises about 50 species in seven genera. My own morphological studies focused on the mouthparts (including labrum, mandible, maxillae, and maxilliped), gill structure, and other external characters. Molecular data of a few species are also available. A cladistic analysis supports the monophyly of the Lophogastrida under consideration of representatives of the Mysida, Amphipoda, Anaspidacea, and Euphausiacea as outgroups. Within the Lophogastrida, the genera Eucopia and Gnathophausia as well as a clade comprising Lophogaster, Ceratolepis and Pseudochalaraspidum are supported. The phylogenetic position of the Lophogastrida within the Peracarida is under dispute. A cladistic analysis comprising all major malacostracan taxa supports a monophyletic Peracarida and a basal position of the Mysidacea (Mysida + Lophogastrida) within Peracarida. A supposed "primitive" character in some Lophogastrida, the "incomplete fusion of the 6th and 7th pleon segment" is probably a derived character.

Richter, S.

Comparative Zoology, Institute for Biology, Humboldt-University Berlin, Philippstr. 13, 10115 Berlin, Germany

The evolution of the optical design in Decapoda Reptantia with particular reference to the Anomala

Any interpretation of the evolution of optical design has to consider not only "physiological constraints" but also given phylogenetic relationships. The reflecting superposition eye has evolved only once, in the ancestral lineage of the Decapoda. Within reptant decapods the most remarkable groups are the Brachyura and the Anomala (= Meiura). In both groups we find representatives with reflecting and parabolic superposition eyes and with apposition eyes. But in spite of these variations, we can still hypothesize a reflecting superposition eye for the stem species of the Meiura since in both taxa some groups possess this eye type. Within the Anomala, the Galatheoidea retained this optical design. Within the hermit crabs, an apposition eye has evolved secondarily and a refracting superposition eye appeared at least once. The stem species of the Brachyura also very likely possessed a reflective superposition eye. The apposition eye evolved secondarily also within the Brachyura.

Ritz, D., Foster, E.M. and Swadling, K.M.

School of Zoology, University of Tasmania, Australia

When pelagic crustaceans go to school the energy savings are more than academic

Many pelagic crustaceans are gregarious and live obligately in swarms and schools. The benefits of this behaviour have long been debated but are generally considered to be protection from predators, facilitation of food finding and capture, reproductive facilitation and energy conservation. While there is some experimental evidence to support the first 3, the last has been almost totally neglected. In this talk I will show that mysids in cohesive swarms consume several times less oxygen per unit mass than those in uncohesive groups. The reason may be that swarming behaviour generates updrafts which minimise the energy needed to resist sinking. Moreover, when forced to perform escape responses, small swarms consumed 50% more oxygen than large swarms. Thus energy conservation could be a potent force selecting for social aggregation.

Robles, R.¹, Schubart, C.D.^{1, 2}, Conde, J.E.^{1, 3}, Carmona-Suárez C.³ and Felder D.L.¹

¹Department of Biology, University of Louisiana, Lafayette, LA 70504-2451, USA ²Present address: Biologie I, Universität Regensburg, 93040 Regensburg, Germany ³Present address: Centro de Ecología, Instituto Venezolano de Investigaciones Científicas (IVIC), A. P. 21827, Caracas 1020-A, Venezuela

Molecular phylogeny of western Atlantic Callinectes Stimpson, 1860, based on two mitochondrial genes

The genus Callinectes (Brachyura: Portunidae) encompasses 15 species of commercially important swimming crabs. Most of these species (9) are from the western Atlantic. Phylogenetic relationships among the species were previously postulated by Norse and Fox-Norse (1979) on a morphological basis. Here we compare mtDNA regions corresponding to the large (16S) and small (12S) ribosomal subunit (~1000bp) to study phylogenetic relationships among the western Atlantic species of Callinectes. We report evidence for two major evolutionary lineages, one of which includes C. bocourti A. Milne Edwards, C. maracaiboensis Taissoun, C. rathbunae Contreras and C. sapidus Rathbun. A second lineage is comprised of C. danae Smith, C. exasperatus (Gerstaecker), C. larvatus Ordway, C. similis Williams and C. ornatus Ordway. C. bocourti and C. maracaiboensis share common haplotypes of 16S mt DNA, and their species status is questioned. The inclusion of the eastern Pacific C. arcuatus Ordway allowed us to calibrate a molecular clock and approximately date speciation events within Callinectes.

Rocha, C.E.F. and Lotufo, G.R.

Department of Zoology, University of São Paulo, São Paulo, Brazil

Diversity of psammic harpacticoids (Copepoda) of the intertidal zone of beaches of the State of São Paulo, Brazil

Intertidal psammic meiofauna of beaches on the northern coast of the state of São Paulo (23(30'- 24(00'S, 44(50'- 45(40'W) was sampled by sieving water accumulated at the bottom of holes dug in sand at ebb tide through a 90 (m-mesh net. Fourteen species of harpacticoids have been identified up to now. We report the first records of members of Afrolaophonte (Laophontidae), Amphiascus (Diosaccidae), Cristacoxa (Cristacoxidae), Kliopsyllus (Paramesochridae), Oniscopsis (Tetragonicipitidae), Zausodes (Harpacticidae) and Filexilia (Ameiridae) from Brazil. The distribution of Arenosetella (Ectinosomatidae), previously known only from the northeastern Brazil (latitude 8(S), was extended far southward by the find of 2 species in São Paulo. The identification of 3 new species of Arenopontia (Cylindropsyllidae) increases to 5 the number of species of this genus on the Brazilian coast. Two additional species, Phyllopodopsyllus setouchiensis (Tetragonicipitidae), previously recorded from Japan and Costa Rica, and the cosmopolitan Laophonte cornuta (Laophontidae) were found. All species are described and illustrated.

Rodríguez, E.M.¹, López Greco, L.S.¹, Medesani, D.A.¹, Laufer, H.² and Fingerman, M.³

¹Department of Biological Sciences, University of Buenos Aires, Argentina ²Department of Molecular and Cell Biology, The University of Connecticut, Storrs, Connecticut 06268, USA ³Department of Ecology and Evolutionary Biology, Tulane University, New Orleans, Louisiana 70118, USA

Effect of methyl farnesoate, alone and in combination with other hormones, on ovarian growth of the red swamp crayfish, Procambarus clarkii, during vitellogenesis

The effect of methyl farnesoate (MF) on the ovaries of female red swamp crayfish, Procambarus clarkii, undergoing vitellogenesis, was determined both in vivo and in vitro. The in vivo assay showed a positive effect of MF on oocyte growth when injected alone and in combination with 17(-estradiol, but not in combination with JHIII or 17(-hydroxyprogesterone. A higher level of incorporation of labelled leucine was induced by MF, on isolated pieces of ovary. The same effect was seen when ovary and mandibular organ were co-incubated. These results suggest that MF stimulated the synthesis of vitellin in the ovary of crayfish. In vitro, 17(-hydroxyprogesterone completely suppressed the stimulatory action of the MO on the ovary, suggesting a competitive inhibition between 17(-hydroxyprogesterone and MF on the ovary and/or a negative feedback by that steroid on the MO.

Rodríguez, E.M.¹, Medesani, D.A.¹, López Greco, L.S.¹ and Fingerman, M.²

¹Department of Biological Sciences, University of Buenos Aires, Argentina ²Department of Ecology and Evolutionary Biology, Tulane University, New Orleans, Louisiana 70118, USA

Effects of some steroids and other compounds on ovarian growth of the red swamp crayfish, Procambarus clarkii, during early vitellogenesis

The effects of spiperone, a dopaminergic receptor blocker, the terpenoid JHIII and the steroids 17(-hydroxyprogesterone and 17(-estradiol (10-7 mol/crayfish) were assayed in vivo, on females of the red swamp crayfish Procambarus clarkii during early vitellogenesis. All these compounds were injected twice a week for three weeks. The rate of molting was determined. Also, at the end of the experiment the ovaries were dissected out, in order to determine the gonadosomatic indexes and the oocyte diameters. Only spiperone and 17(-hydroxyprogesterone were able to produce a significant increase of oocyte growth, probably due to spiperone causing a decrease in the secretion of GIH/MOIH from the eyestalks, and this steroid having a direct stimulatory effect on vitellogenin production. Concerning molting, only JHIII had a significant effect, a stimulatory one, with respect to the controls (p<0.05), producing 100 % molting rate.

Rodríguez, L.J.¹, Lemus, M.¹ and Chung, K.S.²

¹Departamento de Biología, Escuela de Ciencias, Universidad de Oriente, Cumaná ²Instituto Oceanográfico de Venezuela, Cumaná 6101, Venezuela

Energy Content in Somatic and Reproductive Tissues of Emerita portoricensis (Crustacea: Decapda) under Natural Environments

The protein, triglyceride, and glycogen levels of the gonads, gills, hepatopancreas, egg mass and muscle of the mole crab Emerita portoricensis were analyzed during different stages of egg development in the community of San Luis Beach. Four stages of development were characterized regarding the egg mass matured, namely: I Bright Orange Egg Mass (BOEM); II Dull Orange Egg Mass (DOEM); III Brown Egg Mass (BEM) and IV No Egg Mass (NEM). The gonadosomatic index and the levels of triglyceride, protein and glycogen were determined by color techniques. The triglyceride and the protein had a wider variation than the glycogen levels. The triglyceride content in hepatopancreas was higher in the DOEM condition, and gonadal protein was higher in the BOEM stage. The biochemical composition of the tissues reflects a different mobilization of the substrates as the eggs mature.

Sandford, F.R.

Department of Biology, Coe College, Cedar Rapids, Iowa, USA

Population Dynamics and Epibiont Associations of Hermit Crabs on Dog Island, Florida from 1992 to 2001

Periodic belt transects and daily shoreline surveys in January and June/July over a 10-year period were used to study the six species of hermit crabs most common in the upper intertidal zone of a bay with a 960 m shoreline at the East end of Dog Island, Florida, and their association with three common shell epibionts in the area: the Florida hermit-crab sponge, Pseudospongosorites suberitoides, the cloak anemone, Calliactis tricolor, and the hydrozoan Hydractinia echinata. Of 15,052 hermit crabs sampled, Pagurus longicarpus, Pagurus pollicaris, and Pagurus impressus were prevalent in January (88% of all animals) and Clibanarius vittatus dominated in the summer (86% of all animals). The following associations were highly significant: P. impressus with P. suberitoides, P. pollicaris with H. echinata, and Petrochirus diogenes with C. tricolor. C. vittatus rarely had anemones. P. impressus were never found in shells with H. echinata and showed a significant tendency to become stranded, whether in shells or sponges, compared to other pagurid species.

Sankarankutty, C., Cunha, I.M.C. da, Duarte, F.T. and Maia, M.

Museu do Mar "Onofre Lopes", Universidade Federal do Rio Grande do Norte, Natal, Brazil

Utility of incubators for hatching of brachyuran (Crustacea : Decapoda) larvae from eggs

Methodology for the culture of brachyuran larvae has been treated by many authors (Provenzano, 1967; Rice & Williamson, 1970; Bookhout & Costlow, 1981 and Ingle, 1992). Improvement of techniques, knowledge on food requirements and development of adequate culture medium have contributed to the success of larval culture. Past studies have obtained larvae from females maintained in an aquarium. Costlow & Bookhout (1960) and Sankarankutty et al. (1999) have succeeded in hatching larvae from eggs detached from females. Success in the culture of brachyuran larvae was also achieved through the use of incubators designed as a free flowing or closed system (Sastry, 1970; Ebert et al., 1974; Sandifer et al., 1974; Buchanan et al., 1975; King, 1975; Ingle & Clark, 1977). Two types of incubators, one for culturing eggs in vitro and another for culturing hatched larvae, are presented here. Results from a set of experiments are also presented.

Santos, Francisco F.¹ and Ronquillo, Jesse D.²

¹Bureau of Fisheries and Aquatic Resources, Quezon Boulevard, Quezon City, Philippines ²College of Fisheries, University of the Philippines in the Visayas, Miagao, Iloilo 5023, Philippines

Development and survival of Scylla oceanica Dana larvae in culture media added with dried seawater crystals

The larvae of Scylla oceanica from first zoea (Z1) to megalopa (M) were reared in culture media added with dried seawater crystals to determine the effect on larval development and survival. The culture media with low seawater salinity (10, 15, 20, 25, and 30 ppt) were adjusted to 35 ppt with the addition of dried seawater crystals or common table salt. Natural seawater with 35-ppt salinity was used as control. The survival rate and growth index for larval developmental stage were monitored and correlated with the concentration of major physiological ions like Na⁺, Cl-, Ca²⁺, K⁺, and Mg²⁺ in each treatment. After 19 days, the larvae in the control (35 ppt of natural seawater) molted completely into Zoea-5 (growth index of 5) and gave the highest survival rate of 46±3% (P<0.01). During metamorphosis into megalopa stage after 25 days, there was significant difference (P<0.05) found in the survival rate and growth index values among the treatments. None of the larvae survived in culture media cultured in low saline seawater (10, 15, and 20 ppt). The larvae, which were cultured in media with higher concentration of Ca²⁺ (949 to 1,264 mg/L), K⁺ (27.141 to 41.497 mg/L), and Mg²⁺ (2.7940 to 2.9299 mg/L), showed better survival and higher growth index values as compared to those cultured in media with relatively lower concentration of Ca²⁺ (663 to 783 mg/L), K⁺ (8.238 to 21.476 mg/L), and Mg²⁺ (2.5623 to 2.6852 mg/L). Correlation analysis showed that calcium, potassium, and magnesium contents in the medium were positively correlated with final survival rate (y) as expressed in the following equations: Ca²⁺ ions (y = -29.65 + 0.04294 x Ca²⁺; r = 0.94544); K⁺ ions (y = -11.66 + 0.87056 x K⁺, r = 0.94143); and Mg²⁺ ions (y = -216.3 + 82.611 x Mg²⁺, r = 0.93041).

Sari, A.

Department of Biology, Faculty of Science, University of Tehran, Tehran-Iran

Management program of the Iranian lobsters

There are five species of lobsters in the Iranian coastal waters of Oman Sea including, three spiny lobsters (Panulirus homarus, P. versicolor and P. polyphagus) and two slipper lobsters (Thenus orientalis and Scyllarides squammosus). P. homarus is the dominant species in the area. Since 1990s there has been a steady decrease in the annual catch of the Iranian lobsters. The landed catch in the last 4 years was about 20-40 Mt per year. For decreasing degree of exploitation, some aspects including, the breeding season, onset of maturity, number of broods, condition factor, recruitment, hepatosomatic index and gonadosomatic index were considered from October 1998 to September 1999 in Chabahar, southeast Iran. Breeding occurs throughout the year but more than fifty percent of the lobsters were ovigerous during April to August. By using the data, a new fishing season was established from September to November and finally minimum legal size of 70 mm of carapace length was introduced.

Scelzo, M.A.^{1, 2}, Oppedisano, M.¹ and Christiansen, H.E.³

¹Universidad Nacional de Mar del Plata, Funes 3350, (B7600 AYL) Mar del Plata. Argentina ² Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina ³Instituto Nacional de Investigación y Desarrollo Pesquero, Argentina

The reproductive anatomy of male red prawn Pleoticus muelleri (Bate, 1888) (Decapoda, Solenoceridae) from Mar del Plata, Argentina

P. muelleri is a commercial species endemic of the southwestern Atlantic Ocean. It is an open thelycum species. Spermatophore is transferred externally to the female. The male reproductive tract (system) consists of lobular testes and a pair of vas deferent. The vas deferent contains three distinct regions: a bent proximal and medium section and an enlarged terminal section (terminal ampoule). Spermatozoa are described for the first time for the species and for a Solenocerid shrimp. Spermatozoa have an elongate shape, with one or two spikes. The size of spermatozoa, including the spike, range between 40-50 microns being ten times bigger than common penaeid spermatozoa. The length of the spike is only 20-30% of the spermatozal total length. Male morphological and physiological maturity was analyzed. Morphological maturity was based on the presence of functional petasma. The union of the endopodite of the first pleopodes begins at the size of 40 mm of total length. Physiological maturity was based on the presence of spermatozoa in the lumen of the descendent rami of the vasa deferentia and in the terminal ampoule. Physiological maturity starts at size higher than 50 mmTL.

Schubart, C.D.¹, Cuesta, J.A.² and Felder, D.L.²

¹Biologie I, Universität Regensburg, Regensburg, Germany ²Department of Biology, University of Louisiana at Lafayette, Lafayette, USA

A new brachyuran family from Central America: larval and adult morphology with a molecular phylogeny of the Grapsoidea

Adult and larval morphology of two Central American genera, Glyptograpsus and Platychirograpsus, differ greatly from that of all other genera within the Grapsoidea. Several important morphological characters represent synapomorphies when compared to other grapsoids. Adult males of Glyptograpsus and Platychirograpsus are all strikingly heterochelous with the major chela being conspicuoulsy flattened anteriorly and showing a sub-proximal articulation with the carpus. The distal portion of the male gonopod is uncinate, with a narrowed, elongate terminus. Zoeae of the two genera show a 1,2 setation pattern on the maxillar endopod. A molecular phylogeny of the Grapsoidea, based on 16S mtDNA and including type genera of the five currently recognized (sub)families, confirms that the species of Glyptograpsus and Platychirograpsus together form a well-defined monophyletic unit that is distinct from all other taxa within the Grapsoidea. We therefore describe a new family to accommodate these two genera of crabs.

Seneviratna, A.G.D.H. and Taylor, H.H.

Department of Zoology, University of Canterbury, Christchurch, New Zealand

Ontogeny of osmoregulation in embryos of two intertidal crabs, Hemigrapsus edwardsii and H. crenulatus.

Salinity tolerance, and the capacities for osmoregulation, normal development and hatching were investigated for embryos of two euryhaline intertidal crabs. Development rates and hatching success were similar in post-gastrulation ovigerous crabs continuously exposed to 100 % sea water (34 ‰) and to 50 % sea water. However, development was delayed, or aborted, in eggs exposed from cleavage stages, and to 25 % sea water. The volume of the eggs and the solvent volume fraction increased during development in normal and dilute sea water. In acute experiments on isolated eggs, post-gastrula stages survived (> 95%) hyposaline exposure down to 10 % sea water for > 24 h, and to 1 % sea water for 6 h. In dilute sea water, the embryos were hyperosmotic regulators and showed only minor volume change. Osmoregulatory capacity increased during development. Pre-gastrula stages demonstrated much reduced salinity tolerance and osmoregulatory capacity and volume regulation.

Sheehy, M.R.J.

Biology Department, University of Leicester, University Road, Leicester LE1 7RH, UK

The lipofuscin ageing method: past, present and future

Age determination underpins population dynamics research and stock assessment but remains problematic for most crustaceans. Twenty years ago, G. Ettershank of Monash University, Melbourne, introduced the concept of ageing crustaceans by the concentration of the physiological ageing biomarker, lipofuscin, in their tissues. Here, I review subsequent research on lipofuscin in the Crustacea, including the Brachyura. I outline current thought on the nature of lipofuscin and its quantification with a view to dispelling some persistent misconceptions. Appropriate calibration of the lipofuscin index to chronological age is critical for a realistic outcome and I show the importance of considering individual variation and the complex influence of environmental temperature when designing studies and interpreting results. While the technique has proved much less straightforward than implied by the early literature, recent application to the determination of population parameters and year-class strengths has produced some unique results and highlighted future potential.

Shepard, E.F.¹, Savin, S.C.¹, Robalino, J.², Cuthbertson, B.², Bartlett, T.³, Prior, S.¹, Gross, P.S.², Browdy, C.L.¹ Warr, G.W.² and Chapman, R.W.¹

¹South Carolina Department of Natural Resources, 217 Fort Johnson Rd. Charleston, SC 29412 ²The Medical University of South Carolina, 173 Ashley Ave., Charleston, SC 29425 ³College of Charleston, Charleston, SC U.S.A.

Impact of diseases on shrimp wild stock and genomic approach to understanding shrimp immunity

Disease outbreaks in cultured shrimp pose a major threat to shrimp industry and prompted concern regarding the future of native shrimp species in the U.S. Litopeneaus setiferus and L. vannamei are important commercially and the focus of shrimp research in South Carolina. Not only are shrimp a $26B industry worldwide but wild populations are essential for healthy estuarine ecosystems. A survey of native shrimp species along the coast of southeastern United States in 1999 indicated that a small percentage of native species carry viral diseases. Shrimp mRNA was used to construct cDNA libraries from which EST (expressed sequence tag) analyses were derived and genes identified were used as baseline information. Antimicrobial peptides e.g., penaeidins and the 11.5 kDa antibacterial peptides are being investigated using genomic and proteomic approaches. Up- and down-regulated genes identified using subtractive hybridization in response to WSSV infection are currently being characterized.

Shiel, R.J.¹, Green, J.D.² and Halse, S.A.³

¹ CSIRO Land & Water, MDFRC, PO Box 921 Albury NSW 2640 Australia. ² Department of Biological Sciences, Waikato University, Hamilton, New Zealand ³ Department of Conservation and Land Management, PO Box 51 Wanneroo WA 6946 Australia

Copepods of ephemeral waters in arid and temperate Australia

A diverse copepod fauna recorded from microfaunal surveys of >100 ephemeral sites in the southern Murray-Darling Basin is compared to assemblages recorded from comparable surveys in the W.A. Wheatbelt and Carnarvon Basin. Habitats ranged from fresh to hypersaline, with ephemerality their common feature. Preliminary survey data from an on-going study of episodic rivers in the arid L. Eyre Basin is included. Diaptomids (Eodiaptomus) and a suite of tropical-affinity cyclopoids were recorded in the latter survey, whereas centropagids (Boeckella, Hemiboeckella, Calamoecia) and temperate cyclopoids comprised the eastern and western assemblages of the southern surveys. Most of the copepods identified are endemic or Gondwanan in affinity, with up to six species of calanoid and six of cyclopoid co-occurring in some sites. Long separation of eastern and western assemblages, and subsequent adaptive radiation, has led to a distinctive copepod biogeography for the continent.

Shields, J.D.

Department of Environmental Sciences, Virginia Institute of Marine Science, Gloucester Point, VA, USA

Hematology of blue crabs, Callinectes sapidus, experimentally infected with Hematodinium perezi.

Blue crabs, Callinectes sapidus, infected with Hematodinium perezi show signs of weakness and lethargy and die from handling stress. The hemolymph of heavily infected crabs shows reduced clotting ability, discoloration, and a significant decline in total hemocyte density. Host mortality was investigated and differential hematological changes were assessed in experimentally infected crabs. Mature female crabs were inoculated with H. perezi. Mortalities began after 14 d (median time to death = 30.3 + 1.5 d se) with 86% of infected crabs dying to the disease. Total hemocyte densities covaried signficantly mortality. Hemocyte densities declined precipitously within 3 d of infection and exhibited differential changes in granulocytes and hyalinocytes that lasted throughout the course of infection. Crabs that were refractory to infection (i.e., "immune") did not show hemocytopenia and exhibited significant long-term granulocytemia. Hemagglutination was not affected by infection. Infection by H. perezi caused significant alterations to the hemocyte densities of infected crabs.

Shirley, T.C. and Hoyt, Z.N.

Juneau Center, School of Fisheries and Ocean Sciences, University of Alaska, Fairbanks, USA

Seasonal spatial and bathymetric movements of golden king crab, Lithodes aquispinus, in southeastern Alaska

Golden king crabs support major commercial fisheries in Alaska to 700 m depth, however their movements and habitat are poorly known. We attached ultrasonic transmitters to 26 adult crabs and repositioned them to 6 sites with a manned submersible. Crabs were tracked for 8 days with the sub; subsequent GPS locations were made bimonthly from surface vessels. Mean movement initially was 112 m/d, with a max of 1174 m. By Feb. the longest distance was 38.7 km, with a mean of 13.6 km. Crabs did not move as a unit or have directional trends; dispersion increased with time. Crabs occurred on a variety of habitats; the highest density was in boulder fields. 17 mating pairs of crabs were observed, 13 were in boulders and 3 were on rock walls. Depth or habitats may hinder dispersion, delimit stocks and increase overfishing risk. Funding:West Coast & Polar Regions National Undersea Research Center

Silva, T.M.A.¹, Martins, T.G.² and Calazans, D.³

¹Fundação Estadual de Pesquisa Agropecuária and Programa de Pós-graduação em Oceanografia Biológica da FURG. Cx. Postal 474, Rio Grande, CEP 96.201-900, Brazil ²Scholarship FAPERGS ³Departamento de Oceanografia, FURG

Survival of early larval stages of Callinectes sapidus with different phytoplankton diets under laboratory conditions

The success of most brachyuran larval development and survival depend on their initial diet, considered to be based on zooplankton species. Recent studies with small brachyuran larvae indicate that during the early stages they can develop and survive with phytoplankton diets. The aim of this study is to investigate the survival of first zoeal stage of Callinectes sapidus under phytoplankton diets. After hatching the zoeae were placed individually into compartmented plastic boxes. Four treatments with different phytoplankton species were used: TA=Nannochloropsis oculata; TB=Nannochloropsis oculata +Isochysis galbaNa⁺Anabaena sp.; TC=Anabaena sp. and TD=Nannochloropsis oculata +Isochysis galbana under controlled temperature (22 ±2), salinity of 30-32 and photoperiod of 12:12. Daily 2 ml of each treatment was given to the larvae. The Tukey test shows that TB and TD statistically do not differs until de eleven-day of the experience. Until the third day the survival was high to all treatments (62-70%). On the fifth day in the treatment TC and on seventh day in the TA the mortality was 100%. Larval survive in the treatments TB and TD was only 15 and 13% respectively until the tenth day, but none survive to moult to the second stage.

Small, H.J.¹, Wilson, S.¹, Hagan, P.², Neil, D.M.¹ and Coombs, G.H.²

¹Division of Environmental and Evolutionary Biology, Graham Kerr Building, University of Glasgow, Glasgow, G12 8QQ, Scotland, United Kingdom ²Division of Infection & Immunity, Joseph Black Building, University of Glasgow, Glasgow, G12 8QQ, Scotland, United Kingdom

Diagnosis of Hematodinium species infection in the Norway lobster Nephrops norvegicus by ELISA and PCR

Norway lobsters (Nephrops norvegicus) from the coastal waters of Scotland have been shown to be seasonally infected by a parasitic dinoflagellate of the genus Hematodinium. An enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) technique have been developed for the detection of Hematodinium species infection in the haemolymph and tissues of N. norvegicus. The ELISA is simple to perform yet highly sensitive, with a detection level significantly lower than immunoassay diagnostics developed previously. The PCR method developed has a greater specificity and sensitivity for the Hematodinium species infecting the Norway lobster. Both techniques are capable of detecting patent and sub-patent infections, and are currently being evaluated as tools for studying the incidence, prevalence and seasonality of Hematodinium infection in N. norvegicus and other crustacean hosts.

Smit, N.J.^{1, 2}, Basson, L.¹ and Davies, A.J.²

¹Department of Zoology and Entomology, University of the Orange Free State, Bloemfontein, South Africa ²School of Life Sciences, Kingston University, Kingston upon Thames, UK

Blood, Sex and Disease - The life of a South African gnathiid isopod

The life history of members of the isopod family Gnathiidae has intrigued scientists for more than two centuries. Despite this, detailed information on this aspect of gnathiid biology is only available for six of the more than 170 described species. The intertidal species, Gnathia africana, is found along the South African west and south coasts where the parasitic larvae feed on the blood and lymph fluid of residential intertidal fishes. Resting larvae and adult stages are found in a variety of sponges, tunicates and tubes of serpulid worms. Laboratory work was conducted to elucidate the life cycle of G. africana. It was found that G. africana has three larval stages, consisting of three unfed (zuphea) and three fed (praniza) stages, with the final stage praniza larvae moulting into either male or female adults. Forty days after their last feed as praniza 3 larvae, mature females release stage 1 zuphea larvae.

Smith, Robin J. and Kamiya, Takahiro

Department of Earth Sciences, University of Kanazawa, Kakuma, Kanazawa 920-1192, Japan

The ontogeny of the entocytherid ostracod Uncinocythere occidentalis (Crustacea)

Entocytheridae is a cytheracean family which is known for its commensal mode of life on other crustaceans. However, due to their small size and large sexual dimorphism in the sizes of the carapace, the ontogeny of the entocytherids is poorly understood. This paper documents the basic body plans and pore systems of the carapaces of the entocytherid Uncinocythere occidentalis through ontogeny and compares them with other podocope groups. The development of the maxilla and the pore systems of U. occidentalis are different to that of other podocope ostracods. This indicates that they are phylogenetically distant from most other cytheracean families, possibly differentiating from the others during the early evolution of the cytherids.

Söderhäll, K.

Department of Comparative Physiology, Uppsala University, Uppsala, Sweden

Innate immunity in crustaceans

Invertebrate animals do not have a true adaptive immune system and therefore have to rely on innate immune responses. During evolution, the innate immune system appeared before the adaptive immune system, and some form of innate immune reactions are likely to exist in all multicellular organisms. In contrast to adaptive immunity, innate immune recognition is mediated by germ-line encoded receptors, which also means that each receptor is genetically predetermined and evolved by natural selection to have defined specificties for microbial pathogens.These microbial pattern receptors once they have identified and bound to pathogen-associated molecules such as for example, lipopolysaccharides and peptidoglycans from bacteria or beta-1,3-glucans from fungi they will trigger activation of innate immune responses such as the prophenoloxidase activating (proPO) system present in the blood cells of invertebrates. Activation of the proPO-system is both very rapid and efficient and as low concentration as 10 pg per litre of microbial polysaccharides are enough to trigger activation. Following activation of this enzyme cascade several biological functions will be induced which will aid in the elimination of the foreign intruder. The blood cells are vital for the innate immune responses since they contain the proPO-system, express antibacterial peptides, are involved in the clotting system and are the cells which remove foreign particles and pathogens by phagocytosis or encapsulation reactions. Since virtually nothing is known about the ways in which blood cells are formed and how they differentiate into mature cells we have studied this process in detail in a freshwater crayfish and also succeeded in making a blood cell culture from hematopoetic stem cells, which can be induced to differentiate into mature blood cells in culture. Another important innate immune reaction in invertebrates is the capacity to seal wounds and has only been studied in detail in two invertebrate , the horseshoe crab and in a crustacean.In crustaceans it is very efficient and consists of a clotting protein in plasma, which is polymerised by the blood cell enzyme transglutaminase during the clotting reaction.The invertebrate clotting processes are both structurally and functionally different from that of vertebrates and is above all much more efficient.

Song, S.J.¹, Kim, W.¹ and Chang, C.Y.²

¹School of Biological Sciences, Seoul National University , Korea ²Department of Biology, Taegu University, Korea

A new species of Parastenhelia (Copepoda: Harpacticoida: Parastenheliidae) from Cheju Island, South Korea

A new species belonging to genus Parastenhelia of family Parastenheliidae is described on the basis of specimens of both sexes collected from the shallow, marine, sandy bottoms of Cheju Island, Korea. It is distinguished from the congeners by its situation and length of inner seta on first endopod leg 1, the shape of female leg 5, and the number of seta on leg 5 exopod in male. An emended table of morphological characters for the genus is provided.

Spears, T.¹ and Yager, J.²

¹Department of Biological Science, Florida State University, Tallahassee, FL 32306-1100, USA ²Department of Environmental and Biological Sciences, Antioch College, 795 Livermore St., Yellow Springs, OH 45387, USA

Molecular- and morphological-based phylogenetic analyses of the Remipedia

Remipedes represent a recently discovered and enigmatic class of crustaceans comprising 12 extant species distributed among six genera and two families, the Speleonectidae and Godzilliidae, that are confined to anchialine caves in the Bahamas, Turks and Caicos, Canary Islands, Cuba, the Yucatan Peninsula of Mexico, and the Cape Range Peninsula of Western Australia. Phylogenetic relationships within the Remipedia and between remipedes and other crustaceans are poorly understood. We present the results of cladistic analyses using molecular and morphological data sets to assess relationships among remipede taxa and to test various systematic and biogeographic hypotheses. Preliminary findings using maximum parsimony and mitochondrial 16S ribosomal DNA sequence data for eight of the twelve known species (five species of Speleonectes and one each from Pleomothra, Godzillius, and Godzilliognomus) present species from the Godzilliidae, all from locations on the Bahamas Bank, in a basal position, followed by a Speleonectes clade comprised of species from the Bahamas, Cuba, and the Yucatan Peninsula of Mexico.

Spears, T.¹, DeBry, R.W.² and Abele, L.G.³

¹³Department of Biological Science, Florida State University, Tallahassee, FL 32306-1100, USA ²Department of Biological Sciences, University of Cincinnati, P.O. Box 210006, Cincinnati, OH 45221-0006, USA

The unity of the Peracarida: evidence from nuclear small-subunit ribosomal RNA

Evolutionary relationships among the morphologically diverse orders of peracaridan crustaceans are poorly understood, primarily because phylogenetically informative morphological characters are few. In contrast, phylogenies can be inferred, support for relationships can be investigated, and alternative phylogenetic and systematic hypotheses can be evaluated using the more numerous nucleotide characters from the conservatively evolving nuclear small-subunit ribosomal RNA (SSU rRNA) gene. These results can then be used to interpret the evolution of key peracaridan morphological features. Our previous investigations into a molecular-based peracaridan phylogeny have been updated with the addition of new taxa. Character-based phylogenetic analyses suggest a monophyletic Peracarida that includes the orders Amphipoda, Isopoda, Spelaeogriphacea, Tanaidacea, Cumacea, Thermosbaenacea, the enigmatic Bochusacea, and the suborder Lophogastrida; the suborder Mysida is excluded from this peracaridan clade. This finding is corroborated by the presence, distribution and analysis of expanded SSU rRNA genes (i.e., those that contain inserted regions of hypervariable regions of DNA) for the taxa studied: mysids lack expanded SSU rRNA.

Stanton, J.A., Harris, R.R. and Andrews, M.

Department of Biology, University of Leicester, Leicester, UK

Burrowing behaviour and movements of the signal crayfish Pacifastacus leniusculus (Dana) in the U.K. midlands

The signal crayfish, Pacifastacus leniusculus, is North American in origin and was brought to the U.K. for aquaculture purposes. It subsequently escaped into rivers and streams following the demise of this industry. The mechanics of its burrowing capabilities are described, along with differences in burrow morphology. Significant associations have been found between the clay content of stream bank sediments and crayfish burrow densities. In-lab substrate selection experiments indicate a preference for burrowing in clay over simulated natural 'natural refuges'. Measurements of burrow CO₂, ammonia and pH have been made and show slight hypoxic conditions and elevated levels of ammonia. Crayfish movements have been monitored by means of radio tracking. Results indicate that activity is greatest during and immediately following dusk. When inactive, crayfish stay within their burrow network. Some individuals showed long distance (~150m) movements at night and 'occupied' alternative burrows.

Stapleton, K.L., Long, M. and Bird, F.L.

Department of Zoology, La Trobe University, Bundoora, Australia

Comparative feeding ecology of two cohabiting ghost shrimp species

Trypea australiensis and Biffarius arenosus are two species of ghost shrimp which cohabit the extensive intertidal shores of Western Port, Victoria, Australia. This study compared burrow structure, feeding behaviour and diet selectivity of both species. Previous work has documented that B. arenosus burrows are deep and complex, and indicate a deposit-feeding habit. Structurals analysis of the burrows of T. australiensis indicate that the species is capable of both deposit- and/or suspension-feeding. Both species were observed to deposit-feed, but only T. australiensis exhibited resuspension-feeding behaviours. Sediment particles ingested by both species differed significantly from the particle size structure of the surrounding sediment. Biffarius arenosus showed a significant preference for particles <15.6 µm in size, whilst T. australiensis showed significant avoidance of particles <15.6 µm, and a preference for 15.6-63 µm particles. It appears that T. australiensis and B. arenosus adopt different foraging techniques and that interspecific competition may be reduced by each species preferentially ingesting different sized particles.

Stentiford, G.D.¹ , Neil, D.M.², Coombs, G.H.² and Chang, E.S.³

¹Centre for Environment, Fisheries and Aquaculture Science (CEFAS), Weymouth Laboratory, Barrack Road, The Nothe, Weymouth, Dorset DT4 8UB, UK ²Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow, G12 8QQ, Scotland, UK ³Bodega Marine Laboratory, University of California, PO Box 247, Bodega Bay, California 94923, USA

Parasitism - a model for the generalised stress response in crustacean hosts

The Norway lobster (Nephrops norvegicus) harbours infection by the parasitic dinoflagellate Hematodinium. Various aspects of plasma and tissue biochemistry have been studied in uninfected lobsters and compared to that of lobsters at different stages of infection. Infected lobsters display significant alterations in the concentration and composition of carbohydrates, protein and free amino acids in the plasma. The concentration of the crustacean hyperglycaemic hormone (CHH) in the plasma is significantly increased concomitant with increasing infection severity. The concentrations of storage carbohydrates in the muscle and hepatopancreas of infected lobsters are dramatically reduced, while the free amino acid profile of the muscle is also significantly altered. These biochemical perturbances are similar to those induced by other stressors and suggest that there may be common response mechanisms between parasite-induced stress and environmental stress. The ability to accurately stage Hematodinium infection in N. norvegicus makes this association an excellent model for the study of the crustacean disease and stress responses.

Stentiford, G.D.¹, Feist, S.W.¹, Green, M.¹, Bateman, K.¹, Shields, J.D.², Small, H. and Neil, D.M.