First record of Saurodon (Teleostei: Ichthyodectiformes) in La Mula quarry, Eagle Ford Formation (Upper Cretaceous: Turonian), Múzquiz, Coahuila State, Mexico

  • Jesús Alvarado-Ortega Departamento de Paleontología, Instituto de Geología, Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510 México, D. F., México
  • Alberto Blanco-Piñón Centro de Investigaciones en Ciencias de la Tierra, Universidad Autónoma del Estado de Hidalgo, Km. 4.5 Carretera Pachuca-Tulancingo, 42184 Pachuca, Hidalgo, México.
  • Héctor Porras Múzquiz Paleontólogos Aficionados de Coahuila, A. C., Paseo de los Leones, Km. 2 Carretera 57, Sabinas, Coahuila, México


We describe the first fossil fish of the genus Saurodon found in Mexico. The description is based on a specimen from La Mula quarry, located to the northwest of Múzquiz, Coahuila State. Vertebrates and invertebates of Turonian age had been collected in this outcrop of marble strata belonging to Eagle Ford Formation. The Saurodon specimen preserves a pectoral fin ray, the quadrate, and large parts of both dentaries. Two diagnostic characters of this genus are preserved in both dentary bones: in the lingual surface, the foramens in the base of each tooth extend to the alveolar margin and, the symphysis shows a granular surface. This report expands the paleogeographic distribution of Saurodon, which now is known in the marine sediments deposited in the Cretaceous Interior Sea of Northamerica, from Canada to the Northern Mexico.