ABSTRACT: The small, basically Oriental family Opisotretidae is rediagnosed, reclassified, and shown to comprise the following seven genera, all keyed: Carlotretus Hoffman, 1980, with two species, including Carlotretus triramus sp. n. from southern China; Corypholophus Attems, 1938, with two species, one in Vietnam, the other in the Ryukyus, Japan; Martensodesmus Golovatch, 1987, with eight species, all keyed, including Martensodesmus cattienensis sp. n. from southern Vietnam, as well as Martensodesmus bedosae sp. n. and Martensodesmus spiniger sp. n. from southern China; Opisotretus Attems, 1907, with seven species, all keyed, including Opisotretus beroni sp. n. and Opisotretus hagen sp. n., both from Papua New Guinea, Opisotretus deharvengi sp. n. from Sulawesi, Indonesia, and Opisotretus spinosus
