The Cerro Fortaleza Formation, in older literature described as Pari Aike Formation, is a Late Cretaceous geologic formation of Campanian to Maastrichtian age (although it has formerly been reported to be Cenomanian to Santonian) of the Austral Basin in southern Patagonia, Argentina.
Description The sandstones of the formation were deposited in a fluvial environment. The formation has an estimated thickness of and overlies the Anita Formation, while it is overlain by the La Irene Formation. These formations are considered Campanian and Maastrichtian in age, respectively, making the Cerro Fortaleza Formation aged between them. Paleobiota
The giant titanosaurs Puertasaurus and Dreadnoughtus, the megaraptoran Orkoraptor, the berthasaurid Austrocheirus isasii, and the ornithopod Talenkauen have been recovered from the formation alongside turtles and crocodiles.
Dinosaurs
Ornithischians Ornithischians of the Cerro Fortaleza FormationTaxaSpeciesLocalityStratigraphic unitMaterialNotesImagesAnkylosauria indet. Indeterminate Small isolated osteodermsIguanodontoidea indet. Indeterminate One incomplete maxillary tooth crownOrnithopoda indet. Indeterminate Two isolated caudal centraTalenkauen T. santacrucensis Corro Los Hornos near Lake Viedma. Upper A partial articulated skeleton missing the rear part of the skull, the tail, and the hands An elasmarian ornithopod
Sauropods Sauropods of the Cerro Fortaleza FormationTaxaSpeciesLocalityStratigraphic unitMaterialNotesImagesClasmodosaurusC. spatula Lago Viedma Two incomplete teeth A titanosaur Indeterminate 32 isolated teeth Dreadnoughtus D. schrani Rio La Leona Valley Upper Four incomplete proximal caudals and an incomplete left astragalus A titanosaur PuertasaurusP. reuili Cerros Los Hornos, La Leona Upper A partial skeleton, including four disarticulated vertebrae (one cervical, one dorsal, and two caudal vertebrae) A titanosaur
Theropods Theropods of the Cerro Fortaleza FormationTaxaSpeciesLocalityStratigraphic unitMaterialNotesImagesAbelisauridae indet. Indeterminate An incomplete ziphodont tooth AustrocheirusA. isasii Hoyada Arroyo Seco Upper An incomplete right ulna A ceratosaurian theropodOrkoraptor O. burkei Cerro Los Hornos Upper Several isolated teeth, including two anteriormost, probably premaxillary teeth, left manual phalanx I-1, right, nearly complete fibula, and right ungual. A megaraptoran
Fish Fish of the Cerro Fortaleza FormationTaxaSpeciesLocalityStratigraphic unitMaterialNotesImagesAtlantoceratodus A. iheringi Cerro Los Hornos and Hoyada Arroyo Seco.Four lower tooth plates, one lower tooth plate attached to a partial mandibular bone and four upper tooth plates A lungfish
See also List of dinosaur-bearing rock formations
References
Bibliography