Abstract: Ophiuroids, commonly known as brittle stars, are a speciose member of the benthic community in the Southern Ocean. Additionally, many of these species are thought to possess a circumpolar distribution throughout the region. This talk will present findings from two phylogeographic studies on the species Astrotoma agassizii and Ophionotus victoraie, comparing how their geographic structure relates to traditionally held beliefs of benthic community dispersal abilities within and around the Southern Ocean. These studies utilized a combination of traditional mitochondrial markers and analyses, along with reduced representation genomic techniques, specifically RADseq, to uncover fine scale geographic structure and the first case of genetic connectivity across the Antarctic Polar Front in a benthic invertebrate.
