Revision of Pseudorhaptagnostus Lermontova (?Trilobita, Agnostida)

Abstract

The revision of the type collections on the genus Pseudorhaptagnostus Lermontova, 1940 has shown the validity of the type species. Originally indicated type species P. simplex Lermontova, 1951 appeared to be erroneously combination of cephala and pygidia from different species; recombined set of cephala and pygidia for P. simplex synonymized it with P. punctatus Lermontova, 1940, and therefore renamed the type species as the latter one. Also Pseudorhaptagnostus has shown to differ from its close morphological affinities Neoagnostus, Norilagnostus, Machairagnostus, Idolagnostus. New introduction of their morphological difference allowed us to rearrange the species assignment of these genera.