Amphipod crustaceans were collected at all 55 stations sampled with an epibenthic sledge during two IceAGE expeditions (Icelandic marine Animals: Genetics and Ecology) in 2011 and 2013. In total, 34 amphipod families and three superfamilies were recorded in the samples. Distribution maps are presented for each taxon along with a summary of the regional taxonomy for the group. Statistical analyses based on presence/absence data revealed a pattern of family distributions that correlated with sampling depth. Clustering according to the geographic location of the stations (northernmost North Atlantic Sea and Arctic Ocean) can also be observed. IceAGE data for the Amphilochidae and Oedicerotidae were analysed on species level; in case of the Amphilochidae they were compared to the findings from a previous Icelandic benthic survey, BIOICE (Benthic Invertebrates of Icelandic waters), which also identified a high abundance of amphipod fauna.

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JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.

Published and unpublished records of amp hip od-sea anemone associations are reviewed. They involve at least 22 amphipod species in 7 families, and 8 families of sea anemones. The associations are of 4 main types: protection only, ectocommensals, endocommensals and micropredators.Morphological adaptations are not conspicuous, except for the specialised mouthparts of Acidostoma spp., but most obligate symbionts show inborn immunity against the toxic substances released by the host. Sex ratios are normal, sexual dimorphism small, and fecundity low compared to related free-living species.The obligate commensal associates are usually host-specific, although able to survive in alternative hosts in the laboratory, while the micropredators and the facultative associates show low host specificity. The amphipod symbionts usually do not occupy the entire geographical and ecological range of their hosts' distribution.Amphipod-sea anemone associations have evolved independently many times and do not seem to be of great evolutionary antiquity.

Correlations between guillemots (Including Common Guillcmots Uria aalge and Briinnich's Guillemots U. lomuia) and their prey (divided into five prey categories, capelin Mallatus villosus, herring CIupea harengus, polar cod Boreogadus saida, plankton, and a mixture of other prey species) at two depths (10-100m and 100-200 rn) were estimated along an extended transect of 3,060 nautical miles (5,667 km) in the Barents Sea in April/May 1986. Spatial concordance was highest during daylight hours when the largest number of birds were seen on water (presumably feeding birds). Capelin was the single prey category which was most often associated with birds but no single prey category could alone explain the distribution of birds. Although only a small fraction of guillemots could be identified to species, there was some evidence that capelin were of greater importance lo Common than to Briinnich's Guillemots. Overall correlation between birds and total prey density was statistically significant at the smallest scale of 5 nautical miles (nm.). The removal of herring from the calculations increased the strength of the correlation. The depth at which prey was located had little effect on the distribution of birds. The correlation between birds and prey was scale dependent, and reached a maximum at 90 n.m., although there seemed to be some upper threshold in the coefficient at c. 40 n.m. Numerical concordance (including only 5 n.m. periods wherc both prey and birds were present) was significant at the 5 n.m. scale but was higher for high density than for low density prey patches. The results are discussed in relation to thc few similar studies in other oceans and in relation to the severe reduction of important prey species in the Barents Sea.

Amphipods constitute an abundant part of Icelandic deep-sea zoobenthos yet knowledge of the diversity of this fauna, particularly at the molecular level, is scarce. The present work aims to use molecular methods to investigate genetic variation of the Amphipoda sampled during two IceAGE collecting expeditions. The mitochondrial cytochrome oxidase subunit 1 (COI) of 167 individuals originally assigned to 75 morphospecies was analysed. These targeted morhospecies were readily identifiable by experts using light microscopy and representative of families where there is current ongoing taxonomic research. The study resulted in 81 Barcode Identity Numbers (BINs) (of which >90% were published for the first time), while Automatic Barcode Gap Discovery revealed the existence of 78 to 83 Molecular Operational Taxonomic Units (MOTUs). Six nominal species (Rhachotropis helleri, Arrhis phyllonyx, Deflexilodes tenuirostratus, Paroediceros propinquus, Metopa boeckii, Astyra abyssi) appeared to have a molecular variation higher than the 0.03 threshold of both p-distance and K2P usually used for amphipod species delineation. Conversely, two Oedicerotidae regarded as separate morphospecies clustered together with divergences in the order of intraspecific variation. The incongruence between the BINs associated with presently identified species and the publicly available data of the same taxa was observed in case of Paramphithoe hystrix and Amphilochus manudens. The findings from this research project highlight the necessity of supporting molecular studies with thorough morphology species analyses.

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