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Polar Crustacea show high taxonomic and functional diversity and hold crucial roles within regional food webs. Despite the differences in the evolutionary history of the two Polar regions, present data suggest rather similar species richness, with over 2,250 taxa recorded in the Antarctic and over 1,930 noted in the Arctic. A longer duration of isolated evolution resulted in a high percentage of endemic species in the Antarctic, while the relatively young Arctic ecosystem, subjected to advection from adjacent seas, shows a very low level of endemism. Low temperatures and seasonal changes of food availability have a strong impact on polar crustacean life histories, resulting in their slow growth and development, extended life cycles, and reproduction well synchronized with annual peaks of primary production. Many species, Antarctic amphipods in particular, exhibit a clear tendency to attain large size. In both regions, abundant populations of pelagic grazers play a pivotal role in the transport of energy and nutrients to higher trophic levels. The sea-ice habitat unique to polar seas supports a wide range of species, with euphausiids and amphipods being the most important in terms of biomass in the Antarctic and Arctic, respectively. Deep sea fauna remains poorly studied, with new species being collected on a regular basis. Ongoing processes, namely a decline of sea-ice cover, increasing levels of ultraviolet radiation, and invasions of sub-polar species, are likely to reshape crustacean communities in both Polar regions.

Knowledge about sexual segregation and gender-specific, or indeed individual specialization, in marine organisms has improved considerably in the past decade. In this context, we tested the "Intersexual Competition Hypothesis" for penguins by investigating the feeding ecology of Gentoo penguins during their austral winter non-breeding season. We considered this during unusual environmental conditions (i.e. the year 2009 had observations of high sea surface and air temperatures) in comparison with the long term average at Bird Island, South Georgia. Through conventional (i.e. stomach contents) and stable isotopic values from red blood cells, plasma and feathers of both male and female Gentoo penguins, we showed that there were significant differences between sexes, with males feeding mainly on fish (54% by mass) followed by crustaceans (38%) whereas females fed mainly on crustaceans (89% by mass) followed by fish (4%). Themisto gaudichaudii was the most important crustacean prey for males (64% by mass; 82% by number; 53% by frequency of occurrence) and females (63% by mass; 77% by number; 89% by frequency of occurrence), contrasting with all previous studies that found Antarctic krill Euphausia superba were generally the main prey. Stable isotopic data showed that, in terms of habitat use (based on δ 13C), there were significant differences in short-term carbon signatures between males and females (based on plasma and red blood cells), suggesting that both sexes explored different habitats, with females exploring more offshore pelagic waters and males feeding more in coastal benthic waters. Based on δ 15N, males fed on significantly higher trophic level than females (based on plasma and red blood cells), in agreement with our diet results., Thus, Gentoo penguins behave in a similar manner to other non-breeding penguins species (e.g. king, macaroni and rockhopper penguins), albeit at a smaller spatial scale (as they do not disperse as these other penguins do), in that they have a wider habitat and trophic niche during the Antarctic Winter (in comparison to Summer). We also detected individual specialization in feeding/trophic levels for each gender, with certain males feeding mainly on fish and certain females mainly on crustaceans, which may be driven the prevailing environmental conditions that lead individuals to search for alternative prey, and cause sexual diet segregation. Our results provide further information to help improve understanding about sexual segregation and individual specialization of marine organisms, while contributing valuable information on the winter diet for Antarctic monitoring programs and for modelling Antarctic marine food webs.

Are there widespread peracarid species in the deep sea (Crustacea: Malacostraca)?The global zoogeographic distribution of the most widespread peracarid species occurring in three or more ocean basins below 2000 m is analysed. Basing on the published data we investigated 45 peracarid species, which have a most widespread distribution and most likely are cosmopolitan. Thirty-three species have a wide distribution in the Northern Hemisphere. Most species occur in the North Atlantic, however, 16 of these species occur also in the North Pacific, a more limited number of species occurs in the South Atlantic or South Pacific The Southern Ocean displays some special zoogeographic features and 22 widespread species occur there below 2000 m, including highly eurybathic ones. In total, 11 of the analysed species occur in all oceans.Eucopia australis(Lophogastrida),Munneurycope murrayi(Isopoda) andEurythenes gryllus(Amphipoda) are the species with the widest distributions. Other peracarids occurring in all oceans are: the isopodsParamunnopsis oceanicaandEurycope sarsi, the mysidCaesaromysis hispidathe lophogastridEucopia unguiculata, the amphipodMesopleustes abyssorumand the tanaidsExspina typica, Paranarthura insignisandPseudotanais nordenskioldi. No cumacean species has been reported with an ocean-wide distribution butCampylaspis glabraoccurs in the Atlantic, Indian and Pacific oceans. Among plenty of rare species in each order there are only few species with wide distribution records. There is evidence from molecular genetic studies that some of the widespread peracarids represent several cryptic species, however, some,e.g. Eucopia australis, seem to be truly cosmopolitan species. Geography of sampling is biasing our view of biogeography. The history and quality of taxonomic work as well as the reliability of geo- graphic records (quality control of large databases) limits our investigations of widespread or cosmopolitan species as much as the limited knowledge of variation within most species causes difficulties in defining morpho-species with certainty.

In Antarctic waters, the superfamily Lysianassoidea is one of the most important amphipod groups both in terms of species number and abundance. Dominant members of this superfamily are species of the orchomenid complex, found throughout the Southern Ocean. This study presents the first molecular phylogenetic analysis based on a representative subset of the Antarctic species belonging to different orchomenid genera and hence provides a framework for a systematic revision of these taxa. The current classification of the orchomenid genera is mainly based on mouthpart morphology. The validity of these morphological characters was assessed by resolving phylogenetic relationships using nuclear 28S rRNA and mitochondrial cytochrome oxidase subunit I sequences. The molecular data rejected most of the previously proposed taxonomic subdivisions within this complex. The genera Abyssorchomene and Orchomenella as well as the subgenus Orchomenopsis appeared to be non-monophyletic. This implies that the supposed diagnostic characters are likely a result of convergent evolution. Further, our results indicated the necessity of a revision of the family-level systematics.

Summary 1. The Pleistocene glaciations during the Quaternary appear to have resulted in an impoverished groundwater fauna in northern Europe. Re-colonisation may have occurred either through long-distance dispersal from unglaciated southern areas or from local refugia. 2. The Belgian groundwater fauna was sampled at multiple sites, and its habitats characterised, to assess whether the composition of present-day stygobiotic assemblages can be attributed to either of these mechanisms. 3. A total of 202 sampling sites were selected in four hydrogeographic units of the Meuse River catchment. Sites were equally divided among the saturated and unsaturated zones of fractured aquifers (karst) and within the hyporheic and phreatic zones of porous aquifers. Seventeen environmental parameters were determined in parallel. 4. More than 140 species were recorded, including representatives of the Amphipoda, Cladocera, Copepoda, Hydrachnidia, Isopoda, Oligochaeta, Ostracoda, Mollusca, Syncarida and Nematoda. Thirty stygobiont species were identified, of which 10 species were new to the Belgian fauna, raising the total number of stygobiotic species in Belgium to 41. 5. The frequency of occurrences of stygobiotic species was always low, with 37% of the sampled sites lacking stygobionts. A few species were exclusive to one hydrological zone, although no statistically significant differences were detected in species richness at any of the four hierarchial levels considered (Meuse catchment = region, hydrogeographic units, aquifer type and hydrological zone). 6. Overall, results suggest that the stygobiotic fauna of Belgium is species-poor and mostly comprises widely distributed species with broad ecological tolerances. This supports the view that eurytopic species re-colonised the area by long-distance dispersal from refugia in southern Europe. The virtual absence of endemic species further suggests that the scenario of an ancient fauna that survived in local refugia is of minor importance.

Summary 1. A possible conservation strategy to minimise the risk of groundwater biodiversity loss due to human activities consists in designing a network of reserve areas at the continental scale that collectively include most groundwater species. To this end, we compared the efficiency of three area selection methods (species richness hotspots, endemism hotspots and complementarity) and examined the influence of spatial constraints (reduced extent and increased aggregation of reserve areas) on the representation of 1059 groundwater species in six European regions. 2. Presence data from a data base elaborated as part of a European initiative on groundwater biodiversity, the PASCALIS project, were referenced onto 4675 grid cells (0.2 by 0.2°). Complementary performed much better than traditional selection methods for maximising species representation in a reserve network arbitrarily limited to 10% of all the cells containing groundwater fauna. It captured 155 more species than areas selected on richness and 77 more species than areas selected on endemism hotspots. 3. Representing species in a specified proportion of their area of occupancy (i.e. 100%, 50% and 10% of the area of occupancy of species occurring in 1, ≤10, and >10 cells, respectively) required inclusion of 46% of the cells containing groundwater fauna. The reserve network needed to achieve this level of coverage may be too large and fragmented to be implemented and managed in practice. 4. Reduction of the reserve areas to 10% of the landscape containing groundwater fauna and their aggregation into a smaller number of cell clusters resulted in a more realistic reserve network that represented 73.8% (782 species) and 59.1% (274 endemics) of the total number of species and endemics, respectively. 5. We propose several research priorities to improve the design of effective groundwater reserve networks in Europe: (i) devising sampling strategies that reduce uncertainties in the placement of reserves and increase the number of alternative reserve networks and (ii) shifting from a grid-cell selection approach to an aquifer-selection approach that incorporates species representation targets, minimum space requirement and also socio-economic costs related to the vulnerability of aquifers and degree of human activity in the catchment.

The assemblages inhabiting the continental shelf around Antarctica are known to be very patchy, in large part due to deep iceberg impacts. The present study shows that richness and abundance of much deeper benthos, at slope and abyssal depths, also vary greatly in the Southern and South Atlantic oceans. On the ANDEEP III expedition, we deployed 16 Agassiz trawls to sample the zoobenthos at depths from 1055 to 4930m across the northern Weddell Sea and two South Atlantic basins. A total of 5933 specimens, belonging to 44 higher taxonomic groups, were collected. Overall the most frequent taxa were Ophiuroidea, Bivalvia, Polychaeta and Asteroidea, and the most abundant taxa were Malacostraca, Polychaeta and Bivalvia. Species richness per station varied from 6 to 148. The taxonomic composition of assemblages, based on relative taxon richness, varied considerably between sites but showed no relation to depth. The former three most abundant taxa accounted for 10‐30% each of all taxa present. Standardised abundances based on trawl catches varied between 1 and 252 individuals per 1000m 2 . Abundance significantly decreased with increasing depth, and assemblages showed high patchiness in their distribution. Cluster analysis based on relative abundance showed changes of community structure that were not linked to depth, area, sediment grain size or temperature. Generally abundances of zoobenthos in the abyssal Weddell Sea are lower than shelf abundances by several orders of magnitude. r 2007 Elsevier Ltd. All rights reserved.

The Register of Antarctic Marine Species (RAMS) is a marine species database that manages an authorita- tive taxonomic list of species occurring in the Southern Ocean. RAMS links with several other initiatives managing biogeographic or genomics information. The current paper aims to briefly present RAMS and provides an updated snapshot of its contents, in the form of a DarwinCore checklist (available through http://ipt.biodiversity.aq/resource.do?r=rams) and illustrative barplots. Moreover, this article presents a ten year appraisal (since the creation of RAMS). This appraisal first focuses on RAMS bibliometrics. We observed that RAMS was cited (Google Scholar) in 50 distinct publications among which 32 were peer- reviewed in 18 different journals. Three journals (Antarctic Science, Polar Biology, ZooKeys) represent al- most 40% of these peer-review publications. The second appraisal focuses on the evolution of new RAMS records. We observed an important decrease in data additions since 2011. As a case study, we focused on an original dataset for a specific group (Asteroidea, Echinodermata). It appears that around one hundred species of asteroids are lacking in RAMS despite the relatively high availability of these data. This suggests that the users’ community (or collaborative projects such as AquaRES) could be helpful in order to main- tain the RAMS database over the long term., SCOPUS: ar.j, info:eu-repo/semantics/published

234Th is considered a valuable and useful tracer of oceanic biogeochemical processes occurring over timescales of days to weeks. While the geochemical behaviour of this radionuclide in the marine environment is well known, relatively few studies have explored its interactions with biota. To better understand biologically related 234Th dynamics, bioaccumulation of 234Th from the dissolved phase and its subsequent retention in small Antarctic crustaceans (the isopod Natatolana oculata and the amphipods Orchomenella ultima and Uristes stebbingi) was determined under controlled laboratory conditions. Despite morphological and behavioural differences, all three species displayed comparable concentration factors (CF ≥ 80) and very long retention of 234Th (biological half-life not significantly different from infinity). From 16% (isopod) to 49% (both amphipods) of accumulated 234Th was associated with the animal soft parts, which is substantial when compared with reported values for other particle-reactive transuranic elements. The relevance of zooplankton as a potential modulator of 234Th distribution in the water column is discussed in light of these findings. CF-based computations suggest that, for typical zooplankton biomass, biologically mediated interactions with particle flux models can be neglected. In contrast, in waters with very high crustacean biomass, such as krill schools, 234Th distribution in the water column would be largely determined by these organisms. In such waters the biological compartment should be addressed as it could confound the reliability of vertical particle flux assessment using 234Th as a proxy.

Peracarid crustaceans form a significant part of the macrobenthic community that is responsible for scavenging on large food falls onto the sea floor. Although several studies are available about scavengers from tropical and temperate seas, very little information has been published about such species living in Antarctic waters, particularly at greater depths. The present paper is based on a collection of 31 baited trap sets deployed in the Weddell Sea, Scotia Sea, and off the South Shetland Islands, and presents results on the geographical and bathymetric distribution of the different taxa and on the eco-functional role of scavengers. Some 68,000 peracarid crustaceans from 62 species were collected. About 98% of individuals belonged to the amphipod superfamily Lysianassoidea, and 2% to the isopod family Cirolanidae. Of these species, 31, including 26 lysianassoids (1400 individuals), were collected deeper than 1000 m. High species richness was discerned for the eastern Weddell Sea shelf compared with other Antarctic areas. The Antarctic slope also seems to be richer in species than other areas investigated in the world, while in the abyss, scavenger species richness appears to be lower in Antarctica. A richness gradient was thus observed from the shelf to the deep. For amphipods, a number of species extend their distribution from the shelf to the slope and only one to the abyssal zone. Amphipod species showed degrees of adaptation to necrophagy. The functional adaptations of the mandible and the storage function of the gut are discussed. Feeding experiments conducted on lysianassoid species collected at great depths and maintained in aquaria showed a mean feeding rate of about 1.4–4.1% dry body weight day−1, which is consistent with data obtained from other species.

In the canals of three species of Antarctic Demospongiae, a new species of Lysianassoidea (Crustacea: Amphipoda) was found. The new species Pseudokoroga spongiophila is described, its ecology is briefly summarized. While the superfamily is represented in the Southern Ocean by 146 species, belonging to 54 genera, Pseudokoroga spongiophila n. sp. is one of the rare species symbiontically living in sponges. Up to 24 individuals were collected in 1000 cm3 of tissue of the host Demospongiae Jophon spatulatus (Kirkpatrick, 1907).

The food and feeding ecology of the 2 closely related species of prions Pachyptila belcheri and P. desolata was investigated over 3 consecutive chick-rearing periods at Iles Kerguelen, the only place where they nest sympatrically in large numbers. In all years, the 2 prion species fed on crustaceans, with a small proportion of mesopelagic fish and squid. The hyperiid amphipod Themisto gaudichaudii was consistently the dominant prey item, accounting for 76 and 70% by number, and 57 and 57% by reconstituted mass of the diet of P. belcheri and P. desolata, respectively. Prions, how- ever, were segregated by feeding on different euphausiids, P. belcheri on Thysanoessa sp. (18% by number and 16% by mass) and P. desolata on Euphausia vallentini (9% by number and 15% by mass). P. desolata also caught more small prey such as copepods (9 vs 1000 km from the breeding colonies, during the chick-rearing period. The stable-carbon and -nitrogen isotopic compositions of chick feathers were identical in both species, indicating no important trophic segregation during the breeding period, when adult birds are central-place foragers. The ratios were, however, different in adult feathers, suggesting moulting in Antarctic waters for P. belcheri and in subtropical waters for P. desolata, i.e. in distinct foraging areas when birds are not constrained to return to the colonies.

Lake Baikal is well known for its exceptional diversity of gammarid amphipods, with 95% of endemics from its 270 described species representing about 20% of the world freshwater fauna. Echiuropus (Asprogammarus) bekmanae n.sp. was collected by an `autonomous trap system', a sampling device thoroughly described here. Although not necrophagous itself, this new species was found in two baited trap samples (at 750 and more than 1600 m) from 1995 and 1996. This rather small (13 mm) deep water species is the eighth species of the subgenus Asprogammarus, of the Baikal endemic genus Echiuropus. Diagnoses of the subgenus and the closer species are given.

Amphipod crustaceans form one of the most diversified animal groups within the Antarctic macrozoobenthos, both from the taxonomic point of view (more than 800 species have been recorded in the Southern Ocean) as by niche occupation and at the community level. Thus, amphipods are likely to play an important role in the organic matter fluxes that occur on the Antarctic sea floor. The dietary behaviour of these peracarids is still poorly known, and only few species have been analysed. This paper describes the trophic preferences of some dominant amphipod species of the Eastern Weddell Sea benthos, deduced from stomach content analyses and behavioural observations in aquaria. More than 1000 specimens, belonging to 40 species (representing 27 genera and 15 families) were dissected; and several thousands of individuals were kept in aquaria for 6–9 weeks and presented with various potential foods. These two approaches revealed at least eight different feeding types: suspension-feeding, deposit-feeding, deposit-feeding coupled with predation, opportunistic predation, micropredatory browsing, macropredation coupled with scavenging, opportunistic necrophagy and true necrophagy. These different behaviours cover almost all the possible feeding types with the exception of macroherbivorous browsing. Among the eight described feeding types, no particular one is dominant. In the same way, types involving microphagy and macrophagy are equally represented. Predatory types (opportunistic or exclusive) account for 64% of the species analysed, while scavenging types (facultative or obligate) account for 60%. The overlap suggests that many amphipod species have a wide dietary spectrum and are able to take advantage of different food resources.

Developments of future scenarios of Antarctic ecosystems are still in their infancy, whilst predictions of the physical environment are recognized as being of global relevance and corresponding models are under continuous development. However, in the context of environmental change simulations of the future of the Antarctic biosphere are increasingly demanded by decision makers and the public, and are of fundamental scientific interest. This paper briefly reviews existing predictive models applied to Antarctic ecosystems before providing a conceptual framework for the further development of spatially and temporally explicit ecosystem models. The concept suggests how to improve approaches to relating species’ habitat description to the physical environment, for which a case study on sea urchins is presented. In addition, the concept integrates existing and new ideas to consider dynamic components, particularly information on the natural history of key species, from physiological experiments and biomolecular analyses. Thereby, we identify and critically discuss gaps in knowledge and methodological limitations. These refer to process understanding of biological complexity, the need for high spatial resolution oceanographic data from the entire water column, and the use of data from biomolecular analyses in support of such ecological approaches. Our goal is to motivate the research community to contribute data and knowledge to a holistic, Antarctic-specific, macroecological framework. Such a framework will facilitate the integration of theoretical and empirical work in Antarctica, improving our mechanistic understanding of this globally influential ecoregion, and supporting actions to secure this biodiversity hotspot and its ecosystem services.Keywords: Environmental change; integrative modelling framework; spatially and temporally explicit modelling macroecology; biodiversity; habitat suitability models(Published: 4 May 2012)Citation: Polar Research 2012, 31, 11091, http://dx.doi.org/10.3402/polar.v31i0.11091 To access the supplementary material to this article: Supplementary Tables S1, S2, please see Supplementary Files in the column to the right (under Article Tools).

A thorough census of Admiralty Bay benthic biodiversity was completed through the synthesis of data, acquired from more than 30 years of observations. Most of the available records arise from successive Polish and Brazilian Antarctic expeditions organized since 1977 and 1982, respectively, but also include new data from joint collecting efforts during the International Polar Year (2007–2009). Geological and hydrological characteristics of Admiralty Bay and a comprehensive species checklist with detailed data on the distribution and nature of the benthic communities are provided. Approximately 1300 species of benthic organisms (excluding bacteria, fungi and parasites) were recorded from the bay’s entire depth range (0–500 m). Generalized classifications and the descriptions of soft-bottom and hard-bottom invertebrate communities are presented. A time-series analysis showed seasonal and interannual changes in the shallow benthic communities, likely to be related to ice formation and ice melt within the bay. As one of the best studied regions in the maritime Antarctic Admiralty Bay represents a legacy site, where continued, systematically integrated data sampling can evaluate the effects of climate change on marine life. Both high species richness and high assemblage diversity of the Admiralty Bay shelf benthic community have been documented against the background of habitat heterogeneity.

Mitotic and meiotic chromosomes of the Antarctic lysianassoid amphipod Waldeckia obesa are described. The modal chromosome number is n = 25 and 2n = 50. The potential applications of cytogenetical studies in this group are discussed.

Epimeria rubrieques sp. n., belonging to the cold water family Paramphithoidae, occurred relatively often in Agassiz and bottom trawls taken during several German Antarctic Expeditions into the eastern Weddell Sea since 1983. Although this species is very conspicuous because of its long mid-dorsal teeth, bright pink-red colour and large size (up to 70 mm), it has only been recorded in the Weddell Sea. The new species is compared to its closest relatives Epimeria macrodonta and E. similis, and an updated key to the 14 species of Antarctic Epimeria is provided. Observations on the general and feeding behaviour of living specimens of Epimeria rubrieques sp. n. in aquaria showed the species to be an ambush predator and a weakly motile epibenthic walker, which swims only rarely.

Trace metals (Cd, Cu, Pb and Zn) were analysed in crustaceans collected on Polarstern cruises ANT XVI/2 (1999) and ANT XXI/2 (2003/04, BENDEX) to the Weddell Sea. Our study provides further evidence for the frequently reported "Cd anomaly" in polar crustaceans, with data ranging from 1.2 (Ceratoserolis trilobitoides) to 6.2 mg Cd kg-1 DW (Notocrangon antarcticus) in 1999 and from 1.2 (Waldeckia obesa) to 20.3 mg Cd kg-1 (Tryphosella murrayi) in 2003. Pb concentrations well below 1 mg kg-1 in most of the samples analysed might serve as a regional or even global background value for comparison in biomonitoring studies. Increasing Cu concentrations from eggs of decapods (e.g., 5 vs. 51 mg kg-1 in N. antarcticus) or juveniles in the brood pouch of an amphipod species to adult females indicate that the enzymatic requirements and haemocyanin component demand for Cu in early life-history stages is probably not met without a distinct bioaccumulation of this essential element after hatching. Most interestingly, Cd also increases (< 0.1 vs. 6.2 mg kg-1 in N. antarcticus). This could be the consequence of efficient uptake mechanisms for Cu that cannot discriminate between this element and Cd. Cu and Zn concentrations in decapods of this study are largely within the range reported worldwide (40-90 mg Cu kg-1 and 40-80 mg Zn kg-1), indicating that these elements are regulated. The enormous heterogeneity of Cd and Zn in many amphipod species investigated (e.g., from 0.6 in Gnathiphimedia mandibularis to 34.4 mg Cd kg-1 in Orchomenopsis acanthura and from 41 in Eusirus antarcticus to 1244 mg Zn kg-1 in Iphimediella bransfieldi) supports the hypothesis of the "Cd anomaly" and suggests that there is probably no consistent metabolic demand for the essential element Zn in this taxonomic group. The heterogeneity of Cu in amphipods is less pronounced.

14 pages, 5 figures, 2 tables Bouvet (Bouvetøya) is a geologically young and very remote island just south of the Polar Front. Here we report samples taken during the RV ‘‘Polarstern’’ cruise ANTXXI/2 on 3 days in November 2003 and January 2004. This work was part of SCAR’s EASIZ programme and intended, by providing data on the marine fauna of this ‘‘white gap’’ in the Atlantic sector of the Southern Ocean, to contribute to identifying the role of Bouvet in the faunal exchange between the Suband high Antarctic. While this goal demands extensive molecular analysis of the material sampled (future work), a checklist of the samples and data at hand widens the faunal and environmental inventory substantially. We suggest some preliminary conclusions on the relationship of Bouvet Island’s fauna with that of other regions, such as Magellanic South America, the Antarctic Peninsula, and the high Antarctic Weddell Sea, which have been sampled previously. There seem to be different connections for individual higher taxa rather than a generally valid consistent picture

We dedicate the present volume to the late Howard Sanders, who passed away after a long illness on 7 February 2001. When as a young scientist at the Woods Hole Oceanographic Institution he, together with his colleague Bob Hessler and his technical assistant George Hampson, collected and analyzed the first “quantitative” samples of deep-sea benthos (today one would call them semi-quantitative), he may not have had any idea how instrumental the resulting time-stability hypothesis would prove to be for at least four decades of biological deep-sea research. The image of the deep-sea floor being a lifeless desert or, at best, a desolate place harboring a depauperate fauna was shattered when investigations along a transect between Bermuda and Gay Head, a cliff on the island of Martha's Vineyard off Massachusetts, revealed that while densities decreased with depth, species richness actually increased. Since then, many more samples have been collected, our knowledge, limited as it may still be, has increased dramatically, and many new theories and hypotheses have been developed. Nevertheless, the work and personality of Howard Sanders are still something one feels obligated to measure up to. With ANDEEP I and II, we may not have entered as much of a terra incognita as Sanders and colleagues did 40 years ago, but our excitement was certainly comparable. We sincerely hope Howard would approve if he could hold this volume in his hands.

Quantitative samples of benthos were taken on a stony beach in the maritime Antarctic (Admiralty Bay, King George Island, South Shetland Islands) during a complete annual cycle. The sampled habitat consisted of cobbles lying on sand and gravel in the fringe between the littoral and sublittoral zones; samples were always taken at low tide just below the water line. In this habitat, abundant macroalgal detritus was observed between stones. This stony beach appeared to be very rich in vagile fauna settled between and under stones. Macrobenthos consisted mainly of amphipods (ca. 85% of total number), gastropods (11%) and nemerteans (3%). The abundance of whole macrofauna ranged to over 50,000 ind. M-2 and its biomass over 600 g m-2 (FW). Seven species of Amphipoda and four species of Gastropoda were found. Amphipoda were dominated by Gondogeneia antarctica (over 70% of all amphipods) and Paramoera edouardi (over 20%), whereas among gastropods Laevilitorina antarctica prevailed (over 70%). Unexpectedly high abundance and biomass of Amphipoda were observed in the first half of winter (May/July), surpassing otherwise important summer amphipod abundance. The probable reason for this phenomenon could be high autumn abundance of decaying algae on the beach in the tidal zone, providing detritus that is probably the main food source for Amphipoda.

Stable isotope (13C/12C and 15N/14N) analyses were performed on 90 species belonging to different benthic communities sampled in the eastern Weddell Sea. The study focused on eight amphipod species whose isotopic composition was compared to their previously described respective gut contents. Amphipod stable isotope ratios correspond fairly accurately to the trophic classification based on gut contents and attest to their wide spectrum of feeding types. Since the fundamental difference between the isotope and the gut content approaches to diet studies is the time scale each method addresses, this coincidence indicates that there would be no significant changes in feeding strategies over time. Three levels of the food web are covered by the eight species and, instead of belonging strictly to one trophic category, amphipods display a continuum of values from the suspension-feeder to scavengers.

Gammaridean amphipods appear ubiquitous in the shelf communities of the eastern Weddell Sea where more than 230 species have been recorded. Comparison of catches of the 40 most common species taken by different gears and ethological observations in the aquarium allowed us to distinguish 6 groups: endobenthic, epibenthic, hyperbenthic (or suprabenthic), benthopelagic, pelagic and cryopelagic. Only epibenthic species, which form the bulk of the fauna, are dealtwith in the present paper. Aquarium observations indicated three different epibenthic strata occupied by amphipods: the sediment surface, and a lower and upper level on the substrata formed by sessile suspension feeders. In addition, four symbiotic microhabitats were detected in or on sponges, ascidians, hydrozoans and gorgonians.

An up-to-date catalogue of Antarctic and sub-Antarctic Phoxocephalidae is presented, including 35 species. Extensive list of bibliographical references with synonymy, detailed information on geographic and bathymetric distribution, ecological data, museum locations of type-material, remarks on taxonomic and biogeographical status, are provided for each species. The catalogue is based on taxonomic and ecological literature until 31 December 2006. Additional unpublished records of species from the Antarctic and sub-Antarctic collections held at the Alfred Wegener Institut für Polarund Meeresforschung, Bremerhaven, and at the Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”, Buenos Aires, have been included. The taxonomic status of all the Southern Ocean species has been checked. Species allocated to the genera Paraphoxus and Parharpinia, and Fuegiphoxus uncinatus require further study to clarify or confirm the genus allocation. Most of the Southern Ocean phoxocephalids have a wide bathymetric distribution, equally present in the Antarctic and sub-Antarctic regions. The highest species richness is found above 200 meters depth in the sub-Antarctic region. Of 35 phoxocephalid species reported, 25 are endemic to the Southern Ocean s.l., 15 are endemic to the Antarctic region and 6 are endemic to the sub-Antarctic region, the latter distributed only in the Magellan province. Endemicity at genus level attains 22% for the whole Southern Ocean, with 3 genera restricted to the Magellan province and one genus to the West Antarctic, Magellan and sub-Antarctic islands provinces. Habitat and substrate preferences, dietary and burrowing behaviours are scarcely known for most of the phoxocephalid species from the Southern Ocean.

Resume De nouvelle recoltes et le reexamen des types d'Ambasiopsis georgiensis K. H. Barnard, A. uncinata K. H. Barnard et Neoambasia tumicornis (Nicholls) ont amene l'auteur a completer et modifier la description de ces especes antarctiques. Sur ces bases, le genre Neoambasia Dahl, 1959, est mis en synonymie avec Ambasiopsis K. H. Barnard, 1931, dont la diagnose est revue.

(1975). Notes sur les Orchomene (Amphipoda, Lysianassidae) de l'Ocean Austral. Journal of Natural History: Vol. 9, No. 4, pp. 457-470.

The revision of the antarctic–subantarctic species Orchomenopsis reducta Schellenberg, 1931, has led to its attribution to a new, highly apomorphic genus: Falklandia gen.n. A new definition of the uristid group is given and Falklandia with 36 other lysianassoid genera are attributed to this supposedly monophyletic group.

French abyssal campaigns SEABED 2 and DEMERABY to the Central Atlantic Ocean collected new specimens of the largest known amphipod Alicella gigantea Chevreux in baited traps and for the first time by bottom trawling. Type material from the Madeira Abyssal Plain is fully redescribed. New Atlantic material and the new Pacific material reported by other authors elsewhere are compared to the types. Some aspects of feeding are investigated and an analysis of the stomach contents of a giant male specimen provides an estimate of minimum feeding rate for this necrophagous amphipod. Les campagnes abyssales francaises SEABED 2 et DEMERABY ont permis de recolter dans l'Atlantique Central, par nasses appâtees et pour la premiere fois par chalutage benthique, de nouveaux exemplaires du plus grand amphipode connu Alicella gigantea Chevreux. Le materieltype de l'espece provenant de la Plaine Abyssale de Madeirc est redecrit en detail et le nouvcau material atlantique lui est compare, ainsi que le nouveau materiel du Pacifique decrit par d'autres. Certains aspects de la nutrition sont abordes et l analyse du contenu stomacal d'un exemplaire male geant a permis d'estimer le taux de nutrition minimum de cet amphipode necrophage.

The antarctic species Adeliella laticornis Nicholls is revised and its descriptions and figures completed. A. olivieri n. sp. from Breidbay, Antarctica, is described. In addition, an abyssal species, previously described as Orchoniene takoradia J. L. Barnard, 1961, is assigned to the genus Adeliella, for which a revised diagnosis is given.