Eodortoka morellana gen. et sp. nov., the first pan-pleurodiran turtle (Dortokidae) defined in the Lower Cretaceous of Europe

Dortokidae is a relatively poorly-known clade of Pan-Pleurodira, exclusively recognized in Europe. It is the only clade of Laurasiatic pan-pleurodirans known in the post-Jurassic record. Its presence has been recognized in several locations and ages. However, only two nominated valid taxa have been described so far: the western European Upper Cretaceous Dortoka vasconica, and the Romanian late Paleocene Ronella botanica. A new dortokid is studied here, Eodortoka morellana gen. et sp. nov. This new taxon is the oldest nominated dortokid, coming from the lower Aptian (Lower Cretaceous) of the Spanish town of Morella. It shows several primitive characters not shared with the so far described dortokids, such as the presence of mesoplastra and the absence of overlap of the second pair of pleural scutes onto the first pair of costal plates. The comparison of Eodortoka morellana gen. et sp. nov. with other specimens allows us to recognize the presence of two members of Dortokidae in the Iberian Lower Cretaceous record. This study shed light on the early evolution of Dortokidae, as well as on the systematic and paleobiogeography of this clade.