Osteology, paleoecology, and phylogenetic relationships of the carettochelyid turtle Allaeochelys crassesculpta from the middle Eocene Konservat-Lagerstätte of Messel, Germany

A detailed osteological analysis of the carettochelyid turtle Allaeochelys crassesculpta from the middle Eocene Messel Pit reveals a unique combination of primitive and advanced traits, providing new insights into the evolutionary history of this group. Using micro-computed laminography and tomography, researchers reconstructed high-resolution 3D models of its skull, shell, and limbs, uncovering features such as an enlarged antrum postoticum and maxilla-quadratojugal contact. The study suggests that Allaeochelys crassesculpta possessed the ability for 'synchronous rowing,' a locomotor mode shared with the extant pig-nosed turtle, hinting at its origins in the Late Cretaceous to Paleocene transition. Additionally, phylogenetic analysis incorporating recent anatomical findings refines our understanding of carettochelyid evolution.

Rollot, Y., Zuber, M., Hamann, E., & Joyce, W. G. (2026). Osteology, paleoecology, and phylogenetic relationships of the carettochelyid turtle Allaeochelys crassesculpta from the middle Eocene Konservat-Lagerstätte of Messel, Germany. Fossil Record, 29(2), 611–674. https://doi.org/10.3897/fr.29.195537