Favotti, Emmanuel ， Ferrero, Brenda S. ， Brandoni, Diego
2015 REVISTA BRASILEIRA DE PALEONTOLOGIA 2015 18(卷), 3(期), (547-554页)
In this contribution a new record of M darwini Owen, based on an incomplete skull (MRHU-1) recovered from the Arroyo Feliciano Formation (late Pleistocene) on the Gualeguay River cliffs, nearly the city of Urdinarrain, is presented. Although the characteristic nasal arch of Mylodon darwini is not preserved at all, the morphology of the preserved portion and the presence of four maxillary lobated alveoli for the molariforms justify its assignment to this species. Based on its geographic and chronologic record, M darwini has been associated to open environments with semiarid and cold climate (e.g. Pleistocene Pampean region and Patagonia of Argentina and Chile) as warm and humid climate (e.g. El Palmar Formation, late Pleistocene, Entre Rios Province; late Pleistocene Arroyo Chui, Brazil). The find of M darwini in the Arroyo Feliciano Formation is important given that it corresponds to the first record of the species for the Formation and the second one for the province. Besides, the presence of M darwini Arroyo Feliciano Formation corroborates the hypothesis that the genus inhabited in warm and humid climates.