Guaibasaurus (“Rio Guaiba lizard”) was another early dinosaur from the Late Triassic, about 220 million years ago. It was found in 1998 by José Bonaparte and Jorge Ferigolo near Candalaria, Río Grande do Sul Province, Brazil. The remains consist of two incomplete skeletons. Guaibasaurus is an even more primitive saurischian than either the Argentinean Herrerasaurus or the Brazilian Staurikosaurus, and may belong to the group that was ancestral to both sauropods and theropods.
