The Siluro-Devonian ostracode genus Nodibeyrichia and faunally associated kloedeniines

The palaeocope ostracode genus Nodibeyrichia Henningsmoen 1954 is shown to be well delimited from Neobeyrichia Henningsmoen 1954. The material from the Siluro-Devonian Beyrichienkalk in the Baltic area comprises two species, N. tuberculata (Klöden 1834) and N. gedanensis (Kiesow 1884); covering the series of Nodibeyrichia forms described by Reuter (1885). Details in the ontogeny and the cruminal metamorphosis of Neobeyrichia are described, and it is shown that beyrichiine ostracodes, in addition to the adductorial scar, have a well developed muscle scar in the anterior part of the preadductorial lobe. Increased knowledge of Frostiella species makes the type material of F. plicata unidentifiable, and this species is declared a nomen dubium. The larger part of the material earlier referred to this species constitutes F. pliculata n. sp.; F. cornuta n. sp. is also described. Neobeyrichia spp. and Kloedeniinae occur together in certain combinations characteristic of faunistic subdivisions of the Beyrichienkalk.