Neuroanatomía de <i>Lohuecosuchus megadontos</i> en el XVI Annual Meeting de la EAVP

Dentro del simposio acerca de la evolución de los crocodilomorfos que tuvo lugar en el pasado XVI Annual Meeting de la EAVP, A. Serrano Martínez presentó una comunicación describiendo las cavidades internas del cráneo de Lohuecosuchus megadontos, especie procedente del yacimiento conquense de Lo Hueco. A partir de las reconstrucciones de dichas cavidades, se pudieron también realizar una serie de mediciones para estimar algunas de las capacidades neurosensoriales y cognitivas de este animal. Aquí el resumen:

The Campanian-Maastrichtian fossil site of Lo Hueco (Cuenca,Spain) has yielded abundant remains of eusuchian crocodylomorphs. Two species have been recently defined on the basis of specimens found at Lo Hueco: Agaresuchus fontisensis and Lohuecosuchus megadontos. They are members of the clade Allodaposuchidae, which comprises exclusively European species and represents one of the closest outgroups to Crocodylia.

The holotype of Lohuecosuchus megadontos is a nearly complete skull. We CT scanned it and reconstructed all its inner cavities in three dimensions. Although the specimen has undergone some deformation during diagenesis, its endocranial anatomy was amenable to digital reconstruction.

The brain and inner ear cavities, the nervous and vascular canals, as well as the morphology of the tympanic and pharyngotympanic systems and of the paranasal sinuses were compared to those of extinct and extant eusuchians, most of them belonging to the three main lineages of Crocodylia. The presence of several plesiomorphic character-states for Eusuchia, such as a flat caudodorsal surface of the cerebrum, huge lateral expansions of the intertympanic recess and a long medial pharyngeal recess, is consistent with Lohuecosuchus megadontos being an early-branching eusuchian.

The inner skull cavities of Lohuecosuchus megadontos were also quantified and analyzed to evaluate its sensory and cognitive capabilities. Our work suggests that Lohuecosuchus megadontos had neurosensorial capabilities similar to those of extant crocodilians, such as an acute sense of olfaction and a hearing most sensitive to low frequencies.