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 dinosaurs were the dominant predators inmost Mesozoicera terrestrial ecosystems1. Early theropod evolution is currentlyinterpreted as the diversification of various carnivorous and cursorialtaxa, whereas the acquisition of herbivorism, together with thesecondary loss of cursorial adaptations, occurredmuch later amongadvanced coelurosaurian theropods1,2. A new, bizarre herbivorousbasal tetanuran from the Upper Jurassic of Chile challenges thisconception. The new dinosaur was discovered at Ayse´n, a fossillocality in the Upper Jurassic Toqui Formation of southern Chile(General Carrera Lake)3,4. The site yielded abundant and exquisitelypreserved three-dimensional skeletons of small archosaurs. Severalarticulated individuals ofChilesaurus at different ontogenetic stageshave been collected, as well as less abundant basal crocodyliforms,and fragmentary remains of sauropod dinosaurs (diplodocids andtitanosaurians).