The Las Águilas site near Porvenir de Jalpa, Coahuila, Mexico, is extremely rich in tetrapod remains comprising both bones and trackways of several dinosaur taxa of late Campanian age. Within a 50 m thick section we identified at least nine layers with dinosaur bone assemblages. In one of these the dinosaur bones are associated with remnants of eusuchian crocodilians, turtles, plesiosaurs, pterosaurs, tyrannosaurids, dromaeosaurids, parksosaurid, hadrosaurids, ceratopsids, and ankylosaurs. This layer is also rich in coprolites of turtles, crocodilians and likely theropods, thus providing evidence for the wealth of Late Cretaceous vertebrate life in the area. 

Confident attribution of bipedal tridactyl dinosaur tracks to theropods or ornithopods can be challenging. Here we describe trackways produced by tetanuran dinosaurs, previously attributed to hadrosaurs, from Coahuila State, northeastern Mexico. Multiple trackways headed in the same direction suggest gregarious behaviour in these late Campanian theropods.