The genus Coryphodon in Europe: contribution of new exceptional material from Le Quesnoy (northern France, early Eocene, MP7 )

Pantodonts are an extinct group of herbivorous eutherian mammals. They comprise 8 families and 23 genera, ranging from the early Paleocene to the late Eocene, including Bemalambda , Barylambda , Titanoides , or Pantolambda . In Europe, only one genus is known, Coryphodon , represented by three species: C. eocaenus , C. anthracoideus and C. oweni . The Le Quesnoy material (Oise, northern France; MP7) described here, offers the first opportunity to evaluate both intraspecies variability and species diversity of the genus Coryphodon in Europe. With more than 150 dental and postcranial specimens, it constitutes the most important assemblage for the genus on the continent. Our examination of this material shows an overlap in the previously proposed diagnostic character states distinguishing C. eocaenus , C. anthracoideus and C. oweni (M 3 entoconid more or less expressed, M 3 lingual cingulum continuous or discontinuous). Moreover, a biometric approach indicates an overlap of body‐size ranges between these three species, whereas this character was presumed diagnostic. Our results therefore support the synonymy of C. anthracoideus and C. oweni with the type species Coryphodon eocaenus Owen 1845, which should consequently be recognized as the sole European species of Coryphodon . Finally, we conducted the first cladistic and Bayesian phylogenetic analyses of Coryphodontidae. These analyses indicate that the genus Coryphodon is paraphyletic and reveal a trend toward specialized bilophodonty within the family, a tendency especially marked in the later Asian genera ( Eudinoceras , Asiocoryphodon , Hypercoryphodon and Heterocoryphodon ).