The evolutionary history of cetaceans is documented by a rich fossil record tracing their origin to the early Eocene of the Indo-Pakistani region, which is considered the cradle of the group. By the middle to late Eocene, cetaceans achieved a global distribution, indicating a dispersal phase during the Lutetian. Western Africa, with its Lutetian deposits, likely played a central role in one of the earliest dispersal events of this group, acting as a pivot between the Indo-Pakistan region and the Americas. Among Paleogene cetaceans, the paraphyletic family Protocetidae stands out as the most diverse group, whose diversification and dispersal played a major role in the evolutionary history of cetaceans. Protocetids were the first to reach Western Africa and the Americas and their retention of an amphibious lifestyle holds significant ecological importance. Recent expeditions in Togolese outcrops have led to the discovery of numerous protocetid remains (articulated skeletons ans isolated remains including abundant teeth) in Lutetian phosphate deposits. New X-ray microtomography techniques, combined with traditional comparative anatomy, enabled thorough and non-destructive analysis of both the external and internal structures of these fossil remains. Most protocedid-bearing localities known so far yielded a single protocetid species each, with exceptions in Pakistan, Egypt, and South Carolina (USA), where two or three species are known to co-occur. In Togo, the situation appears even more complex with three to four forms identified, depending on whether dental or auditory characteristics are considered. This level of protocetid diversity is remarkable for Western Africa, considering that only one species has been identified in either Nigeria and Senegal. While Morocco might have hosted up to three coexisting species, only one has been clearly identified to date. Here, we present the anatomical description of a newly discovered large protocetid from Togo. This new form is represented by several individuals, including nearly complete cranio-dental remains. One specimen is remarkably well preserved, featuring a complete skull and numerous postcranial elements. By studying these more complete fossil remains, we aim to enhance our understanding of protocetid taxonomic diversity at both regional (Western Africa) and global scales.
| Type : | : | Oral |
| Thématiques | : | 8.4 Paléobiologie |
| PDF version | : |  PDF version |
