Tanysauria

Tanysauria (meaning "long lizards") is an extinct clade long-necked archosauromorph reptiles from the Triassic period of Europe, Asia, North America, and South America. It comprises the families Tanystropheidae and Trachelosauridae (found by the authors to be coextensive with Dinocephalosauridae, and a senior synonym of the latter). Within the Archosauromorpha, Tanysauria represents the sister group to the Crocopoda. It contains many of the species formerly placed in "Protorosauria", which is now thought to be a paraphyletic group.

Classification
In their 2024 redescription of Trachelosaurus, Spiekman and colleagues named Tanysauria as a new clade containing the Tanystropheidae and Trachelosauridae (a senior synonym of Dinocephalosauridae). This clade is the sister taxon to the Crocopoda. The results of their phylogenetic analyses are shown in the cladogram below: