Cumaceans (Crustacea) from the Bellingshausen Sea and off the western Antarctic Peninsula: a deep-water link with fauna of the surrounding oceans

摘要

During the austral summers of 2003 and 2006, two cruise were carried out in the Bellingshausen Sea and west off Antarctic Peninsula on board of RV Hesperides. Samples were collected at 26 stations with a multinet Macer-GIROQ sled. A total of 557 cumaceans belonging to 36 species of five families were collected. Nannastacidae was the most abundant and speciose family. Hemilamprops pellucidus and Cyclaspis gigas were the most frequently collected species (38.5% of sampling stations). Cutnella asutralis reached the highest density (514.7 individuals/ 1,000 m~2 at stn 7). Maximum species richness (S = 15) and diversity (H' = 3.53) was observed at one of the deepest station. Positive correlations were found between the cuma-cean distribution and the organic content and percentage of coarse sand of the sediments. Predominance of Nannastacidae in front of other cumaceans could be explained by their type of feeding (i.e. predators or scavengers), which may be more successful in the deep seafloor of an oligotrophic sea such as studied herein. The presence in the deepest sampling sites of species shared with faunas of surrounding oceans suggests a link between these faunas and those of deep Antarctic waters.