Biodiversity and biogeography of Antarctic copepods

A census of pelagic copepods identifies 346 species from 38 families (i.e. 16.7% of all copepods). Among them, 289 species are considered “cosmopolitan” and 57 “endemic”. Most of the species were described in the late 19th or early 20th century. However, due to a resurgence of interest in biological diversity, a large number of exhaustive revisions at various taxonomic levels have recently been initiated. One hundred and thirteen documents covering the census and distribution of copepod species are analysed. The distribution of species in the South Seas is given for 24 sectors chosen in relation to the geographical coordinates of the South Atlantic, South Pacific and Southern Indian oceans and their location with respect to the Antarctic Convergence or the continental shelf. The respective roles of Lagrangian displacement, of the hydrological features characterising the Southern Ocean and of the general ocean currents are emphasised to explain the scattered distributions of the species. Twenty-one species are catalogued as bipolar, 46 species as specifically sub-Antarctic and 222 cosmopolitan ones are probably from sub-tropical/temperate regions.