Walter Joyce, Virginie S. Volpato‡, Yann Rollot‡© Walter Joyce, Virginie S. Volpato, Yann Rollot. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Citation:
Joyce W, Volpato VS, Rollot Y (2018) The skull of the carettochelyid turtle Anosteira pulchra from the Eocene (Uintan) of Wyoming and the carotid canal system of carettochelyid turtles. Fossil Record 21(2): 301-310. https://doi.org/10.5194/fr-21-301-2018 |  |
Here we document the morphology of the only known skullof a carettochelyid turtle from North America. The specimen originates fromthe middle Eocene (early Uintan) Washakie Formation of Sweetwater County,Wyoming, and is referred toAnosteira pulchra based on temporal considerations. The skull ofAnosteira pulchra broadly corresponds in its morphology to that ofother carettochelyids but exhibits numerous differences that are related toit being more gracile. As a meaningful outgroup is lacking, it is not possible to determine if the gracilemorphology seen in this taxon is apomorphic or plesiomorphic for theAnosteira–Allaeochelysclade. Anosteira pulchra and Carettochelys insculpta lackan ossified palatine canal. We conclude by reference to extant trionychidsthat the palatine (mandibular) canal is likely present but branches from thecerebral (pseudopalatine) canal following its exit from the sella turcica. Asin trionychids, the vidian branch of the facial nerve (VII) ofAnosteira pulchra and Carettochelys insculpta mostlytraverses the palatine.