Stephonyx arabiensis (Crustacea: Amphipoda: Lysianassoidea: Uristidae), a new deep-water scavenger species from the Indian Ocean, with a key to the genus Stephonyx

The amphipod genus Stephonyx Lowry & Stoddart, 1989, consists of nine species. This paper adds a new species from the deep Arabian Sea, Indian Ocean, based on material collected by baited trap at 1864m off the coast of Pakistan. The species can be distinguished from the most closely allied species Stephonyx laqueus (Barnard, 1967) by the weakly excavate palm of gnathopod 2, the pointed lateral cephalic lobe, and the shape of coxa 4. A key to the ten species in the genus is provided.