It has generally been held that the family Encrinuridae contains the four genera Encrinurus, Cybele, Cromus, and Dindymene, though Cromus is sometimes regarded as only a sub-genus of Encrinurus. The distinctive features of Encrinurus and Cybele as usually understood have been described and discussed by many authors, especially Salter, Nieszkowski, and Schmidt, but in 1877, Woodward considered Cybele to be only a sub-genus of Encrinurus. Dindymene is sufficiently distinct from the others to have had generic rank always accorded to it.