[Paleontology • 2020] Geology and Paleontology of the Upper Cretaceous Kem Kem Group of eastern Morocco

in Ibrahim, Sereno, Varricchio, et al., 2020.   DOI: 10.3897/zookeys.928.47517 Artwork by Davide Bonadonna.

Abstract
The geological and paleoenvironmental setting and the vertebrate taxonomy of the fossiliferous, Cenomanian-age deltaic sediments in eastern Morocco, generally referred to as the “Kem Kem beds”, are reviewed. These strata are recognized here as the Kem Kem Group, which is composed of the lower Gara Sbaa and upper Douira formations. Both formations have yielded a similar fossil vertebrate assemblage of predominantly isolated elements pertaining to cartilaginous and bony fishes, turtles, crocodyliforms, pterosaurs, and dinosaurs, as well as invertebrate, plant, and trace fossils. These fossils, now in collections around the world, are reviewed and tabulated. The Kem Kem vertebrate fauna is biased toward large-bodied carnivores including at least four large-bodied non-avian theropods (an abelisaurid, Spinosaurus, Carcharodontosaurus, and Deltadromeus), several large-bodied pterosaurs, and several large crocodyliforms. No comparable modern terrestrial ecosystem exists with similar bias toward large-bodied carnivores. The Kem Kem vertebrate assemblage, currently the best documented association just prior to the onset of the Cenomanian-Turonian marine transgression, captures the taxonomic diversity of a widespread northern African fauna better than any other contemporary assemblage from elsewhere in Africa.

Keywords: Africa, Cretaceous, dinosaur, Gara Sbaa Formation, Douira Formation, paleoenvironment, vertebrate

Predators abound on land, in the air and in water some 95 million years on the shores of northern Africa —as shown by the abundant fossils in the Kem Kem region. Large herbivores, such as the long-necked sauropod Rebbachisaurus, could have been hunted or scavenged by several large predators. Artwork by Davide Bonadonna.

The wealth of aquatic life, including shrimp, bony fish, lungfish and giant lobe-finned coelacanths, supported a remarkable array of predators, including the fish-eating sail-backed Spinosaurus and toothless pterosaur Alanqa soaring overhead. Artwork by Davide Bonadonna.

 Nizar Ibrahim, Paul C. Sereno, David J. Varricchio, David M. Martill, Didier B. Dutheil, David M. Unwin, Lahssen Baidder, Hans C. E. Larsson, Samir Zouhri and Abdelhadi Kaoukaya. 2020. Geology and Paleontology of the Upper Cretaceous Kem Kem Group of eastern Morocco. ZooKeys. 928: 1-216. DOI: 10.3897/zookeys.928.47517