Quebrada Fiera (Mendoza), an important paleobiogeographic center in the South American late Oligocene

This contribution focuses on the main results and present researches on the Oligocene fauna from Quebrada Fiera (Mendoza, Argentina). This vertebrate assemblage is providing new data on the distribution and evolution of South American Deseadan (late Oligocene) mammals. Descriptions of notoungulate Notohippidae and Archaeohyracidae have been recently published. A new genus of notohippid was identified, while most archaeohyracid material was recognized as the same species present in Salla (Bolivia). Studies in progress on other native ungulates (Hegetotheriidae, Interatheriidae, Leontinidae, Homalodotheriidae, Toxodontidae, ? Proterotheriidae, and Pyrotheriidae), metatheria, xenarthra, and rodents from Quebrada Fiera will increase the knowledge of this fauna. Preliminarily, the faunal association appears as a mix of taxa. On the one hand, with Patagonian affinities, on the other hand, related to species known from lower latitudes (Bolivia), together with exclusive taxa such as Mendozahippus (Notohippidae). The ongoing research will allow a better understanding of the role of Mendoza area in the paleobiogeographic and biostratigraphic context of the South American Oligocene mammals.