INIBIOMA   20415
INSTITUTO DE INVESTIGACIONES EN BIODIVERSIDAD Y MEDIOAMBIENTE
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
NEUROANATOMY OF THE ABELISAURID THEROPOD VIAVENATOR: THE MOST COMPLETE RECONSTRUCTION OF BRAIN AND INNER EAR FOR A SOUTH AMERICAN REPRESENTATIVE OF THE CLADE
Autor/es:
PAULINA CARABAJAL, A.; FILIPPI, L.
Lugar:
Buenos Aires
Reunión:
Jornada; 30 Jornadas Argentinas de Paleontología de Vertebrados; 2016
Institución organizadora:
Museo Argentino Bernardino Rivadavia
Resumen:
The braincase of Viavenator Filippi et al. (MAU-Pv-LI-530) was recovered complete and isolated. Although crossed by numerous fractures, the endocranial morphology is perfectly observed using CT scans. In Argentina, abelisaurid partial endocranial morphology is only known for another two Cretaceous forms: Abelisaurus Bonaparte and Novas and Aucasaurus Coria et al. Here, we present the most complete neuroanatomy for a representative of the clade in South America, including all the encephalic structures observed in a theropod cranial endocast, and the inner ear. The general morphology of both, brain and inner ear of Viavenator is markedly similar to that of Aucasaurus, including the angle between forebrain, midbrain and hindbrain, the size and shape of the olfactory tract and bulbs, the size and shape of the flocculus of the cerebellum, and the size, shape and orientation of the semicircular canals of the inner. Comparisons with Majungasaurus Depéret from the Cretaceous of Madagascar indicate that abelisaurids share a characteristic neuroanatomy (e.g., general shape and proportion of the regions of the brain, large olfactory tract and bulbs, similar inner ear morphology, etc.). However, the South American forms differ slightly from Majungasaurus in the posterior orientation of the hindbrain, and particularly the size and shape of the flocculus, suggesting different gaze stabilization capabilities. Nevertheless, further studies are needed to better understand the paleobiological implications of these variations.