Origin and diversification of the amphipod genus Epimeria on the Antarctic shelf

Southern Ocean biodiversity reflects major tectonic, oceanographic and climatic changes that occurred in this region during the last 55 million years. Within the amphipod family Epimeriidae, the genus Epimeria contains 50 known species, whereas the three remaining genera are monotypic. It is distributed worldwide, although its diversity is much higher on the Antarctic shelf. Mitochondrial and nuclear markers are used to reconstruct a general phylogeny of the genus. As previous results showed that Epimeria might be polyphyletic, the monophyly of the genus is first assessed by including a variety of related taxa in the analysis. The extent of genetic structuration characterizing widely ditributed species in the Southern Ocean is evaluated. With the inclusion of extralimital species into the phylogenetic analysis, the study ultimately aims to determine the origin and diversification of Epimeria species on the Antarctic shelf.