Eoraptor

Eoraptor (/ˈiːoʊˌræptər/) was one of the earliest-known dinosaurs, living approximately 231 to 228 million years ago,[1] during the Late Triassic in Western Gondwana, in the region that is now northwestern Argentina. It was a small, lightly-built, basal theropoddinosaur. It is known from several well-preserved skeletons. When first described in 1993, it was considered to be one of the earliest, if not the earliest-known dinosaur. Eoraptor has heterodont dentition, suggesting that it was omnivorous, and that this feeding strategy had evolved early on in dinosaurs.