Systematics and distribution of cumaceans collected during BENTAR-95 cruise around South Shetland Islands (Antarctica)

Abstract

During the BENTART-95 cruise, 24 stations around the South Shetland Islands and Trinity Island, ranging from 45 to 649 m bottom depth, were sampled using a Macer-GIROQ sledge. Alltogether, 1236 specimens of cumaceans belonging to 25 species were captured. Four of them are new species named Cumella emergens, Procampylaspis halei, Campylaspis heterotuberculata and Leucon (Crymoleucon) costatus. Distribution of cumaceans in this area is depth-dependent and the highest diversity was observed at the deeper station. A total of 68 species have been recorded from Antarctic and Subantarctic waters, the greatest part (47 species) were found between 50 and 300 m depth; only 3 species inhabit below 2,500 m depth. Antarctic cumacean fauna shows a high degree of endemism at a specific level (91%), however, only one genus of 19 is endemic. By regions, the Kerguelen Islands have the highest percentage of endemic species (56%). Antarctic cumaceans do not seem to have a common origin, some species could have colonized Antarctica through Scotia Arc (as the genus Campylaspis) or emerged from deep-sea while others may be radiated from Antarctica to lower latitudes (as the species of subgenus Crymoleucon).