Mapusaurus, Coria & Currie, 2006

Coria, R. A. & Currie, P. J., 2006, A new carcharodontosaurid (Dinosauria, Theropoda) from the Upper Cretaceous of Argentina, Geodiversitas 28 (1), pp. 71-118 : 74-75

Mapusaurus n. gen.

TYPE SPECIES. — Mapusaurus roseae n. sp.

ETYMOLOGY. — “ Mapu ” is a Mapuche (local indigenous people) term for Earth. Therefore “ Mapusaurus ” should be translated as “Earth reptile”.

HORIZON AND LOCALITY. — Huincul Formation, Río Limay Group (Cenomanian), of the Neuquén Group. Cañadón del Gato in the Cortaderas area 20 km southwest of Plaza Huincul, Neuquén Province, Argentina (Fig. 1).

DIAGNOSIS. — Mapusaurus n. gen. is a carcharodontosaurid theropod whose skull differs from Giganotosaurus in having thick, rugose unfused nasals that are narrower anterior to nasal/maxilla/lacrimal junction; larger extension of antorbital fossa onto maxilla; smaller maxillary fenestra; wider bar (interfenestral strut) between antorbital and maxillary fenestrae; lower, flatter lacrimal horn; transversely wider prefrontal in relation to lacrimal width; ventrolaterally curving lateral margin of palpebral; shallower interdental plates; higher position of Meckelian canal; more posteriorly sloping anteroventral margin of dentary. Mapusaurus roseae n. gen., n. sp. is unique in that upper quadratojugal process of jugal splits into two prongs; small anterior mylohyoid foramen positioned above dentary contact with splenial; second and third metacarpals fused; humerus with broad distal end and little separation between condyles; brevis fossa of ilium extends deeply into excavation dorsal to ischial peduncle. It also differs from Giganotosaurus in having conical, slightly curving cervical epipophyses that taper distally; axial posterior zygapophyses joined on midline; smaller and less elaborate prespinal lamina on midline of cervicals; remarkably sharp dorsal margin of cervical neural spines; taller, wider neural spines; curved ischiatic shaft; more slender fibula.