Notes on the molluscan genera Clavilithes Swainson, 1840 and Rhopalithes Grabau, 1904 (Gastropoda, Fasciolariidae)

The fasciolariid gastropod genera Clavilithes Swainson, 1840 and Rhopalithes Grabau, 1904 have the same type species and hence are objective synonyms. The situation is complicated by the fact that most authors have used the wrong type species designation for Clavilithes and thus most of the species which are actually Clavilithes (s. str.) have been placed in Rhopalithes. Most of the species presently regarded as Clavilithes (s. str.) must in fact be placed in a different genus or subgenus: Clavellofusus Grabau, 1904 is used for this purpose.