Herrerasaurus ischigualastensis Reig, 1963

Age . Camian.

Occurrence. Ischigualasto Formation, San Juan, Argentina. Diagnosis. Large premaxillary-maxillary fenestra; dorsal part of supratemporal fenestra less than half as wide as ventral part; pronounced suborbital ridge on the jugal; lateral depression on quadratojugal process of squamosal; very slender posterior dorsal process of the dentary.

Remarks. In 1963, Reig described three taxa of saurischian dinosaurs from the Ischigualasto Formation of Argentina as Herrerasaurus ischigualastensis, Ischisaurus cattoi, and Triassolestes romeri . Herrerasaurus (Text-fig. 4e) received relatively little attention until the discovery of a complete skeleton in the late 1980s (Sereno and Novas 1992). The osteology of this taxon was described in detail in a series of papers by Novas (1993), Sereno (1993) and Sereno and Novas (1993). The type specimens of Ischisaurus and Triassolestes, and other theropod specimens from the Ischigualasto Formation described as Frenguellisaurus ischigualastensis by Novas (1986), and cf. Staurikosaurus sp. by Brinkman and Sues (1987), respectively, were referred to Herrerasaurus ischigualastensis (Novas 1993) .