A diverse micro- and macrovertebrate assemblage in the Late Campanian (Late Cretaceous) at Cerro de Angostura near Porvenir de Jalpa, Coahuila, northeast Mexico and its palaeoecological implications
Final Report Abstract
During several years of intensive survey, mapping and sectioning in the Las Águilas area, we succeeded in the excavation of a juvenile hadrosauroid, the first partial skeleton of one individual in the area. We also succeeded in examining a site, LA 14, that yielded an unusually diverse assemblage of late Campanian fossils, namely vertebrates. These not only comprise dinosaur remains but also those of turtles and crocodilians, and a variety of coprolites. We discovered several taxa new to the Las Águilas area and found fossil evidence for taxa hitherto only known from footprints or trackways. Additionally, remains of plesiosaurs and ammonites confirm an estuarine palaeoenvironment. Together with previously found fossil leafs and fructifications as well as characean algae and trackways, the Las Águilas area yields one of the most complete palaeo-ecosystems of Mexico. This environment was subject to about eleven short transgression and regression cycles that influenced the composition of the faunal and floral assemblage, whereby the transgression phases never resulted in a completely marine environment. Our investigation of the Cañada Ancha locality provides evidence for a high-energy deposition regime, in which the long bones of hadrosauroids are aligned more or less parallel to each other, and apparently are oriented in one predominant direction. Invertebrates suggest a late Campanian to early Maastrichtian age of the deposits but in any case younger that those of Las Águilas.
Publications
- 2018. First occurrence of Parksosauridae in Mexico, from the Cerro del Pueblo Formation (Late Cretaceous; late Campanian) at Las Águilas, Coahuila. Boletín de la Sociedad Geológica Mexicana 70, 3: 779-78
Rivera-Sylva, H.E., Frey, E., Stinnesbeck, W., Amezcua, N. & Flores Huerta, D.
(See online at https://doi.org/10.18268/BSGM2018v70n3a10) - 2019. Hadrosaurs from Cañada Ancha (Cerro del Pueblo Formation; upper Campanian-?lower Maastrichtian), Coahuila, northeastern Mexico. Cretaceous Research 104, 104199: 11 pp.
Rybakiewicz, S., Rivera-Sylva, H.E., Stinnesbeck, W., Frey, E., Guzmán-Gutiérrez, J.R., Vivas González, R., Nava Rodríguez, R.L. & Padilla-Gutiérrez, J.M.
(See online at https://doi.org/10.1016/j.cretres.2019.104199) - 2019. Preliminary assessment of hadrosaur dental microwear from the Cerro del Pueblo Formation (Upper Cretaceous: Campanian) of Coahuila, northeastern Mexico. Paleontología Méxicana 8, 1: 17-28
Rivera-Sylva, H. & Barron-Ortiz, C., González, R., Rodríguez, R., Guzman Gutierrez, J.R., Valdéz, F., Dávila, C., Potosí, L. & Potosí, S.
- 2019. Terrestrial vertebrate paleocommunities from the Cerro del Pueblo Formation (Late Cretaceous; Late Campanian) at Las Águilas, Coahuila, Mexico. Palaeovertebrata 42(2)-e1
Rivera-Sylva, H.E., Frey, E., Stinnesbeck, W., Amezcua, N. & Flores Huerta, D.
(See online at https://doi.org/10.18563/pv.42.2.e1)
