ИСТИНА

The Clarion Clapperton Zone (CCZ) in the Northeast Pacific Ocean holds the largest deposits of polymetallic nodules at abyssal depths of 4000-6000 m in the world. These nodules are rock formations containing valuable metals and minerals targeted for mining. Polymetallic nodules support a rich sessile and mobile fauna. Little is known so far on the taxonomy, natural history and biogeography of these deep-sea animals which is vital for accurate assessment of the risk of species extinctions from large-scale mining. One of the most abundant megafaunal groups in the CCZ is the Ophiuroidea (brittle stars), of which Ophiotholia is one of the most common genera found in the area. The genus Ophiotholia has a world-wide distribution and currently holds six species. In order to study the taxonomy of this genus Ophiotholia, material collected from seven scientific cruises to the CCZ was examined. Furthermore, comparative material from all the known species was studied.