20.7.15

El modelo 3D del cráneo de Diplocynodon en el 6th Meeting on Cranio-cervical Systems in Vertebrates


Hace unos días tuvo lugar el 6th Meeting on Cranio-cervical Systems in Vertebrates en Gante, Bélgica, y allí fue uno de nuestros colaboradores a presumir de cerebro... ¡de cerebro de cocodrilo, por supuesto!

En el trabajo presentado se muestra la reconstrucción tridimensional de un cráneo de Diplocynodon tormis. Se describen las cavidades internas, entre las que se encuentran el encéfalo, los nervios craneales, vasos sanguíneos y el sistema faringotimpánico, y se comparan estas estructuras con las de varios crocodiloideos y alligatoroideos para tratar de descifrar los cambios sufridos en estas estructuras a lo largo de la historia evolutiva de Crocodylia.

El abstract del trabajo es el siguiente:

The Spanish Eocene (Lutetian) site of "Teso de la Flecha" (Salamanca) has yielded a wealth of crocodile remains, including a well-preserved braincase of the basal alligatoroid Diplocynodon tormis. The specimen was described more than three decades ago as Diplocynodon aff. gracilis. We CT scanned it and reconstructed the endocast and sinuses, thus improving our knowledge of the evolution of inner cavities in eusuchians. Most of the bones of the left side are missing, so the reconstruction was based mainly on the right half of the endocast. The endocast is similar to those of other mesoeucrocodiles in its sigmoid morphology in lateral view. In dorsal view, the endocast is narrow except at the level of the cerebrum, where it appears inflated. The cerebrum is connected with the olfactory bulbs by long olfactory tracts as in other crocodiles.The optic lobe is only very slightly protruding laterally. There is no delineable evidence of the cerebellum. The collapse of the otic capsule made it impossible to reconstruct the inner ear. The braincase around the mid/hindbrain is pneumatized by a complex network of air-filled cavities. The cavum tympanicum proprium broadly opens laterally at the external auditory meatus. It also presents two caudolateral canals: the wide cranioquadrate canal and the thin siphonial tube. The pharyngotympanic (or Eustachian) tubes are flat, ventrally oriented, bilateral canals that open between the basisphenoid and the basioccipital. The median pharyngeal recess connects with both pharyngotympanic tubes, converge medially, continue ventrally and open between the basisphenoids and the basioccipital. The basisphenoid recess is formed by two ventromedially oriented canals that lead into a single canal that opens in the median pharingeal recess more dorsally than in other crocodiles. This specimen provides useful information to understand the early evolution and sequence of acquisition of endocranial synapomorphies within the Alligatoroidea.

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Más información: 
  • Referencia: Serrano-Martínez, A., Ortega, F. & Knoll, F. Paleoneuroanatomy and pneumatic sinuses of the basal alligatoroid Diplocynodon tormis from the Eocene of Spain. Book of Abstracts of the 6th International Meeting on Cranio-cervical Systems in Vertebrates. Gante. Bélgica (7-10/07/2015).
  • Imagen: En la imagen, Alejandro Serrano delante del póster presentado en el congreso.