UN PUEBLO OLVIDADO Y SU RESURGIMIENTO: PRIMEROS REGISTROS FÓSILES DEL CENOZOICO DE CABO RASO (CHUBUT, ARGENTINA) Y SUS IMPLICANCIAS PALEOBIOESTRATIGRÁFICAS

Abstract

We report for the first time continental fossil mammals and trace from the locality of Cabo Raso (Chubut, Argentina). Among them, the presence of the rodent Soriamys gaimanensis (first record outside of Bryn Gwyn locality) is mentioned, in addition to Eoviscaccia australis and Perimys sp. On the same level, isolated notoungulate teeth (Hegetotheriidae indet. and Pachyrukhinae cf. Pachyrukhos sp.) were found. Moreover, the ichnotaxon Chubutolithes gaimanenesis is reported in an underlying level, this being the third locality in the Chubut Province for which this ichnogenus has been mentioned. These specimens allow us to estimate relative ages for two levels of the Sarmiento Formation (middle Eocene to Early Miocene) in the locality, one of them referable to the Casamayoran South American Land Mammal Age—SALMA— (middle Eocene) and the other to the Colhuehuapian SALMA (Early Miocene). From a faunistic perspective, describing a new locality with levels referable to the Colhuehuapian SALMA in Argentina is relevant due to the geographic restriction compared to other SALMAs (Deseadan or PanSantacrucian). From a geographic perspective, Cabo Raso is the only Early Miocene fossil-bearing locality in the coast of Chubut Province reported so far.