Print ISSN: 0031-0247
Online ISSN: 2274-0333
Hypoplasia: CT-scan or naked eye?
Eocene otoliths (Clinchfield Formation), Georgia
New elephant cranium from early Pliocene Ileret, Kenya
Evolution et extinction des reptiles marins au Mésozoïque
Early adaptive radiation of Theridomorpha
The geologically youngest remains of an ornithocheirid pterosaur from the late Cenomanian (Late Cretaceous) of northeastern Mexico with implications on the paleogeography and extinction of Late Cretaceous ornithocheirids
Eberhard D. Frey, Wolfgang Stinnesbeck, David M. Martill, Héctor E. Rivera-Sylva and Héctor Porras MúzquizKeywords: Coahuila; Late Cenomanian; north-eastern Mexico; Ornithocheiridae; Pterosauria
Ornithocheirid pterosaurs were the largest of the toothed pterodactyloids and had a worldwide distribution, although their fossil record is fragmentary, with the exception of the north-eastern Brazilian Crato and Santana Formations (Aptian, ?Albian, Early Cretaceous). With Istiodactylidae, they were also the only toothed pterosaurs that survived into the Cenomanian (Late Cretaceous), becoming extinct at the end of this period. Here we report on an ornithocheirid metacapus from the Late Cenomanian laminated limestone of north-eastern Mexico discovered about 120 km north-west of Ciudad Acuña, northern Coahuila at the south banks of Rio Bravo. The specimen comprises a fragmentary distal syncarpal, a crushed but complete metacarpal IV, two fragmentary preaxial metacarpals and a possible fragmentary terminal left wing finger phalanx. It represents the geologically youngest known ornithocheirid worldwide. We suggest that ornithocheirid pterosaurs may have become extinct because of massive sea level fluctuations during the mid to late Cretaceous that may have obliterated their breeding sites on coastal plains and low lying islands.
Published in Vol 43-1 (2020)
Terrestrial vertebrate paleocommunities from the Cerro del Pueblo Formation (Late Cretaceous; Late Campanian) at Las Aguilas, Coahuila, Mexico
Héctor E. Rivera-Sylva, Eberhard Frey, Wolfgang . Stinnesbeck, Natalia Amezcua Torres and Diana Flores HuertaKeywords: Campanian; Coahuila; dinosaurs; Mexico.; vertebrates
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.
Published in Vol 42-2 (2019)