An enigmatic plant-eating theropod from the Late Jurassic period of Chile

NOVAS, FERNANDO E.; SALGADO, LEONARDO; SUAREZ, MANUEL; AGNOLIN, F.L.; EZCURRA, MARTIN; CHIMENTO, NICOLAS R.; DE LA CRUZ, RITA; ISASI, MARCELO P.; VARGAS, ALEXANDER; RUBILAR-ROGERS, DAVID

NATURE

NATURE PUBLISHING GROUP

Lugar: Londres; Año: 2015 vol. 522 p. 331 - 334

0028-0836

Theropod dinosaurswere the dominant predators inmostMesozoic era terrestrial ecosystems1. Early theropod evolution is currently interpreted as the diversification of various carnivorous and cursorial taxa, whereas the acquisition of herbivorism, together with the secondary loss of cursorial adaptations, occurredmuch later among advanced coelurosaurian theropods1,2. A new, bizarre herbivorous basal tetanuran from the Upper Jurassic of Chile challenges this conception. The new dinosaur was discovered at Ayse´n, a fossil locality in the Upper Jurassic Toqui Formation of southern Chile (General Carrera Lake)3,4. The site yielded abundant and exquisitely preserved three-dimensional skeletons of small archosaurs. Several articulated individuals ofChilesaurus at different ontogenetic stages have been collected, as well as less abundant basal crocodyliforms, and fragmentary remains of sauropod dinosaurs (diplodocids and titanosaurians).