Además de trabajos sobre la anatomía, sistemática, diversidad y neuroanatomía de tortugas pleurodiras, en las XXXVIII Jornadas de la Sociedad Española de Paleontología se presentó un trabajo sobre miembros del otro linaje que forma parte de la diversidad actual: Cryptodira. Concretamente, el estudio defendido en este congreso era aquel relativo a un esqueleto relativamente completo de una tortuga criptodira marina del Eoceno Inferior de Bélgica. Además de por su excelente preservación, el ejemplar analizado destaca por tratarse de un individuo juvenil. Para su estudio se han revisado las especies de tortugas marinas previamente definidas en los niveles eocenos y oligocenos de ese país, la información sobre varias de ellas siendo actualmente muy limitada. Así, de alguna de esas especies no existe ninguna ilustración, no sólo de material atribuido a las mismas, sino tampoco del holotipo. La revisión del material previamente documentado, y el estudio de numerosos especímenes inéditos, ha sido realizado. Además, para este análisis ha sido también relevante la identificación de otros individuos juveniles, series ontogenéticas de varias especies belgas siendo reconocidas. El resumen de este trabajo es el siguiente:
Until now no turtle remains from the lower Eocene marine deposits of Belgium had been documented, except for the dermochelyid Eosphargis gigas, not formally described. A partial skeleton of a sea turtle attributable to Cheloniidae, from the lower Ypresian Kortrijk Clay Formation of Ghlin (NP10), in the Mons Basin (southern Belgium), is presented here. It corresponds to a juvenile specimen, of very small size (i.e., maximum shell length about 10 cm). Despite the relatively low degree of ossification and the development of large fontanelles, much of its articulated carapace is preserved. Most plastral elements are also identified. In addition to some appendicular bones, the specimen, which has been carefully prepared for its study, preserves a partial skull. This skull has been processed by Computed Tomography to facilitate its detailed analysis. The Belgian record is one of the most relevant records to understand the European cryptodiran Eocene to Oligocene sea turtle systematics and diversity. Although several Belgian Paleogene species were defined, generally more than a century ago, most of these forms are currently poorly understood. In fact, the type material of several of these taxa has been poorly documented or was not figured. In this sense, the validity of some of these species has not been confirmed so far. The type material of these species, deposited at the Institut royal des Sciences naturelles de Belgique (Brussels, Belgium), as well as other unpublished and well-preserved individuals attributable to several of them and that are part of the collection of the same scientific institution, have been analyzed first hand with the aim of perform the comparative analysis with the Ghlin specimen. The study of juvenile individuals of several of these forms is especially relevant for this analysis, given that information on the ontogenetic development of Paleogene Cheloniidae representatives is extremely limited.
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