Pistosaurus

Taxobox
name = "Pistosaurus"
fossil_range = Mid Triassic

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image_width=250px
image_caption = "Pistosaurus longaevus" from the middle Triassic of Europe
regnum = Animalia
phylum = Chordata
classis = Sauropsida
ordo = Plesiosauria
familia = Pistosauridae
genus = "Pistosaurus"

"Pistosaurus longaevus" is an extinct genus of aquatic sauropterygian reptile belonging to the plesiosaur order. It was about 3 m (10 ft) long.

Previously "Pistosaurus" was classified as an advanced nothosaur, the presumed ancestors of plesiosaurs, but it has since been reclassified as a primitive plesiosaur. This makes it the oldest plesiosaur known, and the only one from the Triassic period. "Pistosaurus" shows physical traits of both nothosaurs (palate and body shape) and plesiosaurs (stiff vertebral column). Its flippers and long neck also resembled a plesiosaur's.