Alvarezsaurus

Alvarezsaurus (/ˌælvərɛzˈsɔːrəs/; "Alvarez's lizard") is a genus of small alvarezsaurid dinosaur from the Late Cretaceous period, living inArgentina, approximately 86 - 83 million years ago. Estimates suggest that it measured about 2 meters (6.5 ft) in length and weighed approximately 20 kg (45 lbs). Gregory S. Paul estimated in 2010 its weight at 3 kg and length at 1 m.[1]  It was found in the Bajo de la Carpa Formation and was named by paleontologist José Bonaparte in 1991 after the historian Don Gregorio Alvarez.[2]  The type species is A. calvoi.