Allodaposuchus Nopsca, 1928 (Crocodylia, Eusuchia), from the Late Cretaceous of southern France and its relationships to Alligatoroidea

ABSTRACT

The eusuchian Allodaposuchus is described from Late Cretaceous continental strata of southeastern France. Contrary to recent work involving this genus, a new and more derived position within Eusuchia is proposed in the present study. Allodaposuchus cf. A. precedens from southern France and Allodaposuchus precedens from Romania can be assigned to basal alligatoroids, but their relationship to other basal forms such as Leidyosuchus, diplocynodontids, and other basal globidontans remains unresolved. Most of the inconsistency in the position of Allodaposuchus within alligatoroids may be related to the presence of a laterally open canalis quadratosquamosoexoccipitalis in at least Allodaposuchus precedens from Romania, which also characterizes the basal eusuchian Hylaeochampsa. Although this character remains problematic, the combination of alligatoroid synapomorphies in Allodaposuchus supports its position within Alligatoroidea. The new Allodaposuchus specimen from France suggests the presence of a stock of basal alligatoroids in the Late Cretaceous of Europe, whereas North America and Europe remain equally likely options for the biogeographic origin of the clade.

ACKNOWLEDGMENTS

The author particularly thanks A. and P. Méchin for kindly providing access to and for allowing preparation of the specimen. A. D. Buscalioni, M. Delfino, D. Schwarz-Wing, and the editor J. Müller are acknowledged for their constructive input and for reviewing the manuscript. V. Codrea kindly allowed the use of the photograph of the Oarda de Jos Allodaposuchus. E. Buffetaut is thanked for discussion and recommendations in the initial part of the study. J.E.M. was funded by Le Conseil général de l’Allier.