A DYROSAURID CROCODYLIAN FROM THE CRETACEOUS OLMOS FORMATION OF COAHUILA, MEXICO

The family Dyrosauridae is a group of extinct neosuchian crocodyliforms that lived from Late Cretaceous through Eocene time. Dyrosaurid remains are particularly common in marine and paralic strata of North Africa and South America. The only dyrosaurid previously reported from North America is Hyposaurus, found in New Jersey and Alabama. Recently, the Museo del Muzquiz in Coahuila, Mexico recovered cranial material belonging to two specimens of a longirostrine crocodilian from the Cretaceous Olmos Formation. Features of the mandible in one of the specimens indicate that it pertains to Dyrosauridae. However, the number and placement of the dentary alveoli indicate that it is not referable to Hyposaurus. This specimen appears to represent a species previously unknown from North America, and only the second dyrosaurid thus far reported from the continent.