· The genus Clistolagenophrys

was created by Clamp (1991) for Lagenophrys primitiva, which occurs on one of the endemic species of amphipods in Lake Baikal, Russia (Swarczewsky 1930), because closure of its lorica aperture appears to be effected by a markedly different mechanism than in Lagenophrys (Fig. 6). Clistolagenophrys primitiva retracts the entire loricastome within the lorica to close the aperture with its basal edges instead of pulling the lips together (Swarczewsky 1930). Jankowski (1993) maintained that the lorica aperture of C. primitiva was not fundamentally different from that of Lagenophrys; however, he offered no evidence to support this assertion.