Note
Ophiopaepale Ljungman, 1872 , is revised. Schizoderma Nielsen, 1932, is a junior synonym. Ophiopaepale now includes two species, which form a geminate pair from tropical American waters: O. goesiana Ljungman, 1872, type-species, West Indies and Gulf of Mexico, redescribed herein; O. diplax (Nielsen, 1932), n. comb., type-species of Schizoderma, Gulf of Panama and other eastern tropical Pacific localities. Synonymy was required by the discovery of fragmented dorsal arm plates in O. goesiana and the presence of tables comprising the disc granulation of both species. Ophiopaepale is distinguished from other ophiuroid genera by the division of each ventral arm plate into proximal and distal halves.