First Record of Penelope sp. (Aves, Cracidae) in the Late Pleistocene of Northern Uruguay

We report the first fossil record of the family Cracidae in Uruguay from the Sopas Formation of the Late Pleistocene (Paso del Buey Negro locality, Arapey Chico River, Salto Department). The ulnar morphology of the genus Penelope does not allow definitive species-level identification. However, on the basis of the current geographic distribution, linear dimensions, articular features, and muscle impressions, it is highly likely that this is a specimen of Penelope obscura. At Paso del Buey Negro, numerous mammalian fossils have been recorded, including rodents, perissodactyls, artiodactyls, and xenarthrans, as well as freshwater turtles. This locality is thought to have had a heterogeneous environment with open and forested areas associated with watercourses and a temperate to subtropical climate similar to the region’s current climate. The fossil record of the genus Penelope is significant because these birds are clearly dependent on humid forest, gallery forest, and forest-edge environments, generally at low altitudes, and therefore they are proper paleoenvironmental proxies.