Camerochelys vilanovai gen. et sp. nov., a new pan-cryptodiran turtle in the Early Cretaceous of the Iberian Range (Spain)

Abstract

A new turtle taxon, Camerochelys vilanovai gen. et sp. nov., from Hauterivian–Barremian levels of the eastern Cameros Basin (La Rioja, Iberian Range, Spain), is proposed here. Elements of the shell corresponding to five individuals are assigned to it. Camerochelys vilanovai is a turtle with a low, oval and longer than wide shell. It is diagnosed by a combination of characters that includes, among others, the presence of an ornamentation pattern, restricted to the medial area of the vertebral scutes, and composed of thin, numerous and poorly developed radiating striations; shallow nuchal notch; short, and more than four times wider than long cervical scute; five vertebral scutes, all of them substantially wider than long, the second and third ones being more than two times wider than long, and the fourth one two times wider than long; sagittal contact of the last pair of costal plates; presence of inframarginal scutes; absence of mesoplastra. Camerochelys vilanovai is identified as a member of Pan-Cryptodira not assigned to Eurysternidae, to the clade including representatives of Paracyptodira and Plesiochelyidae, or to the crown group Cryptodira. This new taxon could be a representative of Xinjiangchelyidae, a clade belonging to the stem group of Cryptodira, and identified in the Asian and European record. The description of this new taxon further increases the known diversity of turtles in the Early Cretaceous of the Iberian Range, a region where members of several clades of the stem group of Testudines, Pan-Pleurodira and Pan-Cryptodira have been previously identified.