Herrerasaurus ischigualastensis Reig, 1963

Rauhut, Oliver W. M., 2003, The interrelationships and evolution of basal theropod dinosaurs, Special papers in palaeontology 69, pp. 1-213 : 13-14

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) .

Figures

text-fig. 4. Skull reconstructions of representatives of riassic OTUs in left lateral view, a, Euparkeria capensis, Early Triassic (Scythian-Anisian), Beaufort Group, South Africa; redrawn from Ewer (1965). B, basal ornithischian Lesothosaurus diagnostics, Early Jurassic (Hettangian-Sinemurian), Elliot Formation, Lesotho; redrawn from Sereno (1991b). c, prosauropod sauropodomorph Plateosaurus sp., Late riassic (Norian), Knollenmergel, Germany; based on MB R. 1937. D, Eoraptor lunensis, Late Triassic (Camian), Ischigualasto Formation, Argentina; based on PVSJ 512. E, Herrerasaurus ischigualastensis, Late Triassic (Camian), Ischigualasto Formation, Argentina; redrawn from Sereno and Novas (1993). F, Coelophysis bauri, Late riassic (Norian), Chinle Formation, south-western USA; modified from Paul (1993). G, Lilienstemus lilienstemi, Late riassic (Norian), Knollenmergel, Germany; based on MB R. 2175, unpreserved elements shaded. H, Shuvosaurus inexpectatus, Late riassic (Norian), Dockum Group, Texas, USA; based on TU P 9280. Abbreviations: a, angular; aof, antorbital fenestra; d, dentary; emf, external mandibular fenestra; en, external nares; eo, exoccipital; f, frontal; itf, infratemporal fenestra; j, jugal; 1, lacrimal; m, maxilla; n, nasal; o, orbit; oc, occipital condyle; op, opisthotic; pa, parietal; pd, predentary; pm, premaxilla; pm-mf, premaxillary-maxillary fenestra; po, postorbital; pof, postfrontal; q, quadrate; qf, quadrate foramen; qj, quadratojugal; sa, surangular; saf, surangular foramen; snf, subnarial foramen; sob, supraorbital; soc, supraoccipital; sp, splenial; sq, squamosal; stf, supratemporal fenestra. Scale bars represent 10 mm (a-b) and 50 mm (c-H).