Ankylosaurid (Dinosauria: Thyreophora) osteoderms from the Upper Cretaceous Cerro del Pueblo Formation of Coahuila, Mexico

Abstract

Ankylosaurian dinosaur osteoderms have been discovered in the southeastern part of the State of Coahuila, Mexico, in the township of General Cepeda, in the locality known as El Palmar. The osteoderms were collected from rocks that had been correlated to the Cerro del Pueblo Formation (Late Cretaceous: Campanian) of the Difunta Group. The fossil material includes four dermal scutes and three associated fragments that at present cannot be identified. This is the first description of ostoederms and ankylosaurian material from Coahuila.

Hemipelagic cephalopods from the Maastrichtian (late Cretaceous) Parras Basin at La Parra, Coahuila, Mexico, and their implications for the correlation of the lower Difunta Group

“…This is the case for the Cerro del Pueblo Formation, which is famous for its remarkable variety of marine, brackish, and non-marine fossils that includes caracean algae, plants, gastropods, bivalves, sphenodiscid ammonoids, crustaceans, unidentified fish vertebrae, sawfish, turtles of the family Tryonichidae, crocodiles, mosasaurs, dinosaurs and snakes (e.g. Wolleben, 1977;Vega and Feldmann, 1991;Kirkland and Aguillón-Martínez, 2002;Eberth et al, 2004;Ifrim et al, 2005;Meyer et al, 2005;Rivera-Silva and Espinosa-Chávez, 2006;Perrilliat et al, 2008, and own observations). The unit was interpreted to represent a coastal environment in a regressive phase (Eberth et al, 2004).…”

Middle Jurassic ankylosaur tracks from Mexico

“…Ankylosaurian remains have been collected in Mexico, mainly from northern states such as Baja California, Chihuahua and Coahuila. Among the most common ankylosaur remains found in Mexico are teeth and osteoderms, an isolated vertebra, and a few limb elements have also been found (Rivera-Sylva and Espinosa-Chávez, 2006;Rivera-Sylva et al, 2011;Martínez-Díaz and Montellano-Ballesteros, 2011). Kappus et al (2011) mentions the presence of ankylosaur tracks near Ciudad Juárez, Chihuahua, northern Mexico.…”

Evidence of predation on the vertebra of a hadrosaurid dinosaur from the Upper Cretaceous (Campanian) of Coahuila, Mexico

“…Further south, the Late Campanian fluvial sediments of the Cerro del Pueblo Formation in the the Parras Basin at Las Aguilas and Rincon Colorado have yielded a rich fossil assemblage (HERNÁNDEZ, 1992;HERNÁNDEZ & KIRKLAND, 1993;HERNÁNDEZ et alii, 1996;AGUILLÓN-MARTÍNEZ et alii, 1998;HERNÁNDEZ & DELGADO-DE JESÚS, 2000;BRINKMAN et alii, 2002;EBERTH et alii, 2003;RIVERA-SYLVA & ESPINOSA-CHÁVEZ, 2006;SERRANO-BRAÑAS et alii, 2006;GATES et alii, 2007). Until now, little has been known about the slightly younger northern outcrops of the river system.…”