Two New Lysianassid Species (Amphipoda, Gammaridea) from Coastal Waters of West Sakhalin, Sea of Japan

Abstract

Two new amphipod species of the family Lysianassidae Orchomene gurjanovae sp. nov. and Orchomenella lukini sp. nov. have been found from the Western Sakhalin shelf. Orchomene gurjanovae is similar to 0. minor Bulycheva, 1952, 0. Tschernyschevi Briiggen, 1909 and Orchomenella perdido Lowry and Stoddart, 1997 in having a notched telson; but it differs from the other species by the high flat dorsal keel on the first urosomite. Orchomenella lukini is closely related to 0. pacifica Gurjanova, 1938, 0. japonica Gurjanova, 1962, and 0. thomasi Lowry and Stoddart, 1997 by having the keeled urosomite I and basis of pereopod 7; but differs from them by the shape of notch on the basis of pereopod 7 and the transverse palmar margin of the article 6 of gnathopod 1.