- Project title
- Early Leatherback sea turtle (Dermochelyidae, Testudines) from the basal Eocene phosphatic deposits of Tunisia provides insight about the diversification of this enigmatic group
- Description of the project
- Our project consists in a redescription and a comparative study of early Dermochelyids (leatherback group) from the Ypresian of Gafsa deposits of Tunisia as “Lytoloma” elegans and “Thalassochelys” testei. The aim of its work is to provide new morphological data about the early evolution of this group and improve our knowledge about its relationship within Chelonioids. For this work, we will use an extensive dataset of comparative cranial and mandibular material including current leatherback specimens (Dermochelys coriacea), diverse fossils stem-Dermochelyids taxa as Allopleuron hofmanni, Eosphargis gigas, Eosphargis breineri as well as some protostegids.
The X-ray computed tomography will allow us to get access to internal cranial anatomic features as foramens and canals for the cranial blood circulation system or for the cranial nerve system. This method provides also additional information on inner ear morphology. The inner cranial morphology provides key features for phylogenetic analysis as well for the understanding of evolution, in particular, for this group that show highly unusual traits as a low ossification of the parabasisphenoid (in particular of the rostrum basisphenoidale) or a coalescent canal for the lateral head vein and the internal carotid artery.
This project is a part of my PhD thesis that I currently pursue at Fribourg University that include the study of early evolution of several lineages of Pan-chelonioidea Sea turtles, including redescription of forgotten forms of key taxa, as well as a taxonomic revision of this group for the Cretaceous and Paleogene species. This project is supported by National Swiss Research Founding (SNF).
Works done by the platform AST-RX