Triassic Arizona

Placerias (meaning 'broad body') is an extinct genus of dicynodonts that lived during the Carnian and Norian stages of the Triassic period (230–215 million years ago). Placerias belongs to a clade of dicynodonts called Kannemeyeriiformes, which was the last known group of dicynodonts before the taxon became extinct at the end of the Triassic.

species of plant

Doswellia is an extinct genus of archosauriform reptile from the Late Triassic of North America. It is the namesake of the family Doswelliidae, related to the proterochampsids which were more common in South America. Doswellia was a low and heavily built carnivore which lived during the Late Triassic. It possesses many unusual features, including a wide, flattened head with narrow jaws and a box-like rib cage covered by at least ten rows of bony plates.

Machaeroprosopus (from , 'large knife' and , 'bordering on') is an extinct genus of mystriosuchin leptosuchomorph phytosaur from the Late Triassic of the southwestern United States. M. validus, once thought to be the type species of Machaeroprosopus, was named in 1916 on the basis of three complete skulls from Chinle Formation, Arizona. The skulls have been lost since the 1950s, and a line drawing in the original 1916 description is the only visual record of the specimen. Another species, M. andersoni, was named in 1922 from New Mexico, and the species M. adamanensis, M. gregorii, M. lithodend

geologic formation

genus of amphibians (fossil)

Eotephradactylus (meaning "ash-winged dawn goddess") is an extinct genus of pterosaurs known from the Late Triassic of what is now Arizona, United States. The genus contains a single species, Eotephradactylus mcintireae, discovered in 2011 and named in 2025. It is known from part of the lower jaw, isolated teeth, and possibly a wing bone found in the Chinle Formation, which dates to the Norian age. These bones were found in a bone bed in addition to many other species, including various fish, mammal precursors, turtles, and other reptiles.

Uatchitodon is an extinct genus of Late Triassic reptile known only from isolated teeth. Based on the structure of the teeth, Uatchitodon was probably a carnivorous archosauromorph. Folded grooves on the teeth indicate that the animal was likely venomous, with the grooves being channels for salivary venom. The teeth are similar to those of living venomous squamates such as Heloderma and venomous snakes. Uatchitodon and Microzemiotes are the earliest known potentially venomous reptiles.

Leptosuchus (from Ancient Greek λεπτός (leptós), meaning "thin", and Σοῦχος (Soûkhos), meaning "Sobek") is an extinct genus of leptosuchomorph parasuchid phytosaurs with a complex taxonomical history. Fossils have been found from the Dockum Group and lower Chinle Formation outcropping in Texas, New Mexico, and Arizona, United States, and date back to the Carnian stage of the Late Triassic.

left|thumb|198x198px|A "type A" Tanytrachelos, believed to be a female.

Tecovasuchus is an extinct genus of aetosaur. It is known primarily from osteoderms found from the Tecovas Formation in Texas, which is Late Triassic in age, dating back to the lower Norian. Material is also known from several other localities of the Chinle Group in New Mexico and Arizona, such as older Carnian outcrops and younger Rhaetian outcrops. Specimens of Tecovasuchus have been collected from the Tecovas Formation, the Bluewater Creek Formation, and the Los Esteros Member of the Santa Rosa Formation.

genus of reptiles