Pyrotherium

Pyrotherium ('fire beast') is an extinct genus of South American ungulate, of the order Pyrotheria, that lived in what is now Argentina and Bolivia, during the Late Oligocene. It was named Pyrotherium because the first specimens were excavated from an ancient volcanic ash deposit. Fossils of the genus have been found in the Sarmiento Formation of Argentina and the Salla Formation of Bolivia. Possible South American descendants of the xenungulates, the complete study of the tarsus of Pyrotherium fails to support this relationship. In one study, derived characters were not seen in any mammal examined except the embrithopod Arsinoitherium from the Cenozoic of Africa. Whether this is due to common ancestry, or to the unusual mode of locomotion used by these animals (graviportal and plantigrade) remains to be seen. The vaguely elephant-like Pyrotherium was about 3 metres (9.8 ft) long and stood approximately 1.50 metres (4.9 ft) tall at the shoulders, with an estimated weight of up to 3,500 kg (7,700 lb) for P. romeroi. A recently discovered species, P. macfaddeni was smaller, at under 900 kg (2,000 lb). The living animal's heavy body was carried by robust legs. Pyrotherium also had a short trunk on its snout, and two pairs of flat, forward-facing tusks in the upper jaw, with a single pair in the lower jaw.