The first record of Galea Meyen, 1832 (Rodentia, Hystricognathi, Caviidae) in the late Pleistocene of southern Brazil and its palaeobiogeographic implications

The first caviine rodent referable to Galea Meyen, 1832 is described from the late Pleistocene of southern Brazil based on a left dentary with the p4-m3 series. The specimen derives from the Ponte Velha I locality in the Touro Passo Creek (Touro Passo Formation, upper Pleistocene), western Rio Grande do Sul State. The main characters used to assign this specimen to Galea are: anterior area of horizontal crest at the level of prism I of p4; deep anterior area of masseteric fossa; incisor alveolus on the medial face of the dentary extended up to the level of prism II of m2; and presence of cement in the hypoflexid. Currently, the genus has a disjunct distribution, with a group in Argentina, Bolivia and Peru, and another in northern and northeastern Brazil. The presence of this taxon in Pleistocene deposits of Rio Grande do Sul State, Uruguay and the Argentine Mesopotamian, where there are no extant representatives of the genus, indicates its wider distribution during the late Pleistocene.