Revision of the rhynchonellid brachiopod genus Ripidiorhynchus SARTENAER
Abstract
Many species, subspecies and forms assigned to Ripidiorhynchus SARTENAER 1966 do not belong to it and give it an overextended published stratigraphic range of Givetian to Lower Carboniferous. Eight new genera are proposed: Kedridorhynchus [type species K. cedarensis (STAINBROOK 1942); late Givetian], Poleomesorhynchus [type species P. gregeri (BRANSON 1923); early Frasnian], Hypselororhynchus [type species H. farsani (BRICE 1977); middle-late Frasnian], Porthmorhynchus [type species P. ferquensis (GOSSELET 1887); middle-late Frasnian], Paropamisorhynchus [type species P. kotalensis (BRICE 1971); late Frasnian], Saxulirostrum [type species S. saxatile (HALL 1867); late Frasnian], Piridiorhynchus [type species P. confinium n. sp.; earliest Famennian], Orophomesorhynchus [type species O. huotinus (de VERNEUIL 1845); early Famennian]. Following revision of Ripidiorhynchus a new zone is introduced at the base of the Famennian based on Piridiorhynchus confinium in the southeastern and eastern parts of Dinant Basin. Some attention is also devoted to the alleged overlapping of the Frasnian/ Famennian boundary by Ripidiorhynchus.