Late Permian darwinulocopines (Crustacea: Ostracoda) from the Rio do Rasto Formation, Brazil

The study on Paleozoic podocopid ostracods in Brazil still lags behind the Mesozoic (mainly Cretaceous) and Cenozoic ones, and is mostly concentrated in the Paraná Basin. Consequently, we have only vague information about their diversity, distribution, and affinities to the North Hemisphere assemblages. In order to contribute to the improvement of this knowledge, this work presents a study on Late Permian Darwinulocopina from the Rio do Rasto Formation, Paraná Basin, Brazil. The vertebrate fauna associated indicates a Lopingian age for these deposits which are interpreted as a delta front to delta top environment. Nine species of darwinulocopines were recorded in the studied sample, some of them very abundant, while others very rare and represented only by a few specimens. The superfamily Darwinuloidea is represented by the genera Paleodarwinula Molostovskaya and Wjatkellina Molostovskaya, and the Suchonelloidea is represented by the genera Dvinella Molostovskaya and Prasuchonella Molostovskaya. Two new species are described: Paleodarwinula moliyae nov. sp. and P. gregorysohni nov. sp. Additionally, the occurrence of two species previously described from the Eastern European Platform (Wjatkellina fragiloides Zekina and Prasuchonella sulacensis Starozhilova) and one described in North America (Paleodarwinula hollandi [Scott]) demonstrate possible biostratigraphic and paleoenvironmental comparisons between the Paraná Basin and Russian Platform Assemblages, as well as North American ones.