The large trionychid turtles from the early Eocene record of Belgium

Remains of trionychid turtles are abundant in the early Eocene fossil record of Belgium where several species are recognized. In this context, the remains of several large-bodied individuals, with a shell length of about one meter, stand out both for their size and good preservation. The Royal Belgian Institute of Natural Sciences houses several unpublished large-size specimens, but also others with a high historical value (e.g., those from Erquelinnes and Leval), which had not been, until now, studied in detail. Recent studies proposed that all large trionychids from the Eocene of Western Europe could belong to a single species, attributable to the North American genus Axestemys. However, a valid diagnosis for this putative European single species is not currently available, since the characters that allow its differentiation with each of the North American species have not been well established. Several of the best preserved Belgian specimens have been recently restored, which allows us to perform their detailed study. Thus, the description of several anatomical elements hitherto poorly known or not described for the large-bodied trionychids of the Eocene of Europe can be performed for the first time. The study of the Belgian specimens, which correspond to the most complete and best preserved in Europe, allows us to evaluate the hypothesis on whether they belong to the same species as the other largebodied trionychids found in the Paleogene record of this continent. Thus, this study significantly increases the information on the relatively poorly known Paleogene large trionychids of Europe. This research was supported by network project BR/121/A3/PALEURAFRICA from the Belgian Science Policy Office, and by the Ministerio de Ciencia, Innovación y Universidades (IJCI-2016-30427).

Abstract of an Oral Presentation or a Poster

Paleontology