The Deep-Sea Asellote (Isopoda, Crustacea) Fauna of the Northern Seas: Species Composition, Distributional Patterns and Origin

Publisher Website
Google Scholar
Abstract
The marine asellote (Isopoda, Crustacea) fauna of the Northern Seas, i.e. the Norwegian, Greenland, Iceland and North Polar Seas, contains 106 species. Most of them occur in shallow waters, but the number of species declines rapidly with increased depth. Half the species are endemic and those occurring also outside the Northern Seas are mainly found in the North Atlantic. The endemism of species is low (750 m. Only a single endemic asellote genus is recorded from the Northern Seas. The low diversity of the deep Arctic asellote isopods is explained partly by a short evolutionary time of the fauna within this environment, but in particular due to isolation of the Greenland-Iceland-Faeroe Ridge, which acts asa barrier against the immigration of species into the Northern Seas and thus shapes the species composition. The hydrographic condition above the ridge may also have restricted the migration of deep-sea species into the Northern Seas. Consequently, the Arctic deep-sea asellote fauna consists predominantly of species belonging to less pronounced deep-sea families (e.g. Desmosomatidae and Nannoniscidae) and genera, or shallow water genera occurring in proximity to the Northern waters, while the most pronounced deep-sea families and genera are poorly represented (e.g. families Haploniscidae and Ischnomesidae) or even absent (e.g. genus Storthyngura). The Arctic deep-sea asellote fauna is considered to have originated mainly from the North Atlantic Ocean.

This publication has 0 references indexed in Scilit: