Original paper

Cranial endocast of the carcharodontosaurid theropod Giganotosaurus carolinii Coria Salgado, 1995

Carabajal, Ariana Paulina; Canale, Juan Ignacio

Abstract

A complete endocast of Giganotosaurus carolinii Coria & Salgado, 1995 was made in latex after removing mechanically the sediment filling of the cerebral cavity of the braincase, thereby allowing the description of the endocranial anatomy of the specimen. The endocast was compared with the other few known natural or artificial theropod endocasts, including the two species of the African allosauroid species Carcharodontosaurus saharicus and C. idiguensis. As in Carcharodontosaurus, the olfactory bulbs in Giganotosaurus are aligned with the forebrain, the midbrain is posteroventrally inclined and the hindbrain is parallel but ventral to the forebrain, showing similarly angled cephalic and pontine flexures. The cranial nerves and blood vessels have a similar disposition as in Carcharodontosaurus saharicus. However, in Giganotosaurus there is only one branch for cranial nerve XII, and cranial nerve XI has a separate internal opening from the vagus foramen (metotic foramen). In C. saharicus, there is a separate opening as well, but it is anterior in position and was probably utilized by cranial nerve IX. The length of the endocast of Giganotosaurus, including the olfactory bulbs, is approximately 19 % longer than the endocast in Carcharodontosaurus saharicus.

Keywords

theropodaendocranial cavitypaleoneurology