Preliminary Report on a Late Cretaceous Vertebrate Fossil Assemblage in Northwestern Coahuila, Mexico

A new vertebrate fossil assemblage of Late Cretaceous age is reported here. This discovery represents the results of the 2007 and 2008 field seasons in the locality known as "Las Jicoteas" situated in the municipality of Ocampo, in northwestern Coahuila, Mexico. The stratigraphic sequence where this fossil fauna occurs can be correlated to the Lower Member of the continental Aguja Formation that outcrops in the neighbouring Big Bend region of Texas. This new fauna bears the first record of a nodosaur for Mexico, and, also additional dinosaur remains attributed to the families Tyrannosauridae and Hadrosauridae are recorded. Associated fossil taxa include lepisosteid fishes, turtles and crocodile remains. The palaeocological conditions inferred by this new faunal assemblage suggest a paralic system with prodelta, marshes, lagoons, and nearshore marine deposits.