The fossils from Punta Alta included a nearly perfect head and three fragments of heads of the Megatherium Cuvierii, the jaw of a related species which Owen named Mylodon Darwinii, and jaws of Megalonyx Jeffersonii.
Os fósiles de Punta Alta incluían unha cabeza case perfecta e tres fragmentos de cabezas de Megatherium cuvierii, a mandíbula dunha especie relacionada que Owen denominou Mylodon darwinii, e as mandíbulas de Megalonyx jeffersonii.