Protosauria is an extinct group of archosauromorph reptiles from the latest Permian (Changhsingian stage) to the early Late Triassic (Carnian stage) of Asia, Europe, North America. It was named by the English anatomist and paleontologist Thomas Henry Huxley in 1871 as a order. Other names that are for the most part equivalent to Protorosauria include Prolacertiformes and Prolacertilia.
Protorosaurs are distinguished by their long necks formed by elongated cervical vertebrae, which have ribs that extend backward to the vertebrae behind them. Protorosaurs also have a gap between the quadrate bones and the jugal bones in the back of the skull near the jaw joint, making their skulls resemble those of lizards.
In Walking with... Series
The Triassic segment of this episode featured Tanystropheus - the only prolacertid reptile to be ever featured in any of the IP productions up to date. Tanystropheus was depicted a harmless fish-eater, which could break away its tail and flee from danger - but that was later proven to be incorrect. Tanystropheus died out by the end of the Triassic, approximately 215 MYA.