MACNBR   00242
MUSEO ARGENTINO DE CIENCIAS NATURALES "BERNARDINO RIVADAVIA"
Unidad Ejecutora - UE
artículos
Título:
Orkoraptor burkei nov. gen. et sp., a large theropod from the
Autor/es:
FERNANDO E. NOVAS, MARTÝ´N D. EZCURRA, AGUSTINA LECUONA
Revista:
CRETACEOUS RESEARCH (PRINT)
Referencias:
Año: 2008 p. 468 - 468
ISSN:
0195-6671
Resumen:
A new large theropod, Orkoraptor burkei nov. gen. et nov. sp., from the Upper Cretaceous (Maastrichtian) Pari Aike Formation of southern Patagonia is based on a postorbital, quadratojugal, coronoid?, several teeth, an atlantal intercentrum and neurapophysis, two caudal vertebrae, and the proximal half of tibia. This new theropod exhibits characteristics of maniraptorans (i.e., coelurosaurians more derived than tyrannosaurids) including an upturned rostral process of the postorbital, the caudoventral corner of which is widely concave. Furthermore, teeth without denticles and carina in the mesial margin resemble the condition of the maniraptoran clades Compsognathidae and Deinonychosauria. The new Patagonian theropod differs from other coelurosaurians (Ornithomimosauria, Compsognathidae, Alvarezsauridae, Dromaeosauridae, Aves) in having caudal vertebrae with a single pair of small pleurocoels on each side, and in having a median depression flanked by two longitudinal and narrow furrows on each tooth. Orkoraptor represents one of the southernmost carnivorous dinosaurs yet found in South America and adds valuable information about the diversification of tetanuran theropods in Gondwana.Orkoraptor burkei nov. gen. et nov. sp., from the Upper Cretaceous (Maastrichtian) Pari Aike Formation of southern Patagonia is based on a postorbital, quadratojugal, coronoid?, several teeth, an atlantal intercentrum and neurapophysis, two caudal vertebrae, and the proximal half of tibia. This new theropod exhibits characteristics of maniraptorans (i.e., coelurosaurians more derived than tyrannosaurids) including an upturned rostral process of the postorbital, the caudoventral corner of which is widely concave. Furthermore, teeth without denticles and carina in the mesial margin resemble the condition of the maniraptoran clades Compsognathidae and Deinonychosauria. The new Patagonian theropod differs from other coelurosaurians (Ornithomimosauria, Compsognathidae, Alvarezsauridae, Dromaeosauridae, Aves) in having caudal vertebrae with a single pair of small pleurocoels on each side, and in having a median depression flanked by two longitudinal and narrow furrows on each tooth. Orkoraptor represents one of the southernmost carnivorous dinosaurs yet found in South America and adds valuable information about the diversification of tetanuran theropods in Gondwana.Orkoraptor represents one of the southernmost carnivorous dinosaurs yet found in South America and adds valuable information about the diversification of tetanuran theropods in Gondwana.