Norian genus extinctions

Nothosaurus ('false lizard', from the Ancient Greek and ) is an extinct genus of sauropterygian reptile from the Triassic period, approximately 245–228 million years ago, with fossils being distributed throughout the former Tethys Ocean, from North Africa and Europe to China. It is the best known member of the nothosaur order.

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.

Shastasaurus ("Mount Shasta lizard") is an extinct genus of ichthyosaur from the Late Triassic. Specimens have been found in the United States, Canada, and China.

Poposaurus is an extinct genus of pseudosuchian archosaur from the Late Triassic of the southwestern and eastern United States. It belongs to the clade Poposauroidea, an unusual group of Triassic pseudosuchians that includes sail-backed, beaked, and aquatic forms. Fossils have been found in Wyoming, Utah, Arizona, Texas, and Virginia. Except for the skull, most parts of the skeleton are known. The type species, P. gracilis, was described and named by Maurice Goldsmith Mehl in 1915. A second species, P. langstoni, was originally the type species of the genus Lythrosuchus. Since it was first des