Sapheosaurus (also known as Piocormus) was a sphenodontid of the suborder Homoeosauria, although its skull was longer and narrower than that of Homoeosaurus. It was classified as a genus of sapheosaurid by Michael Benton in 1985. It reached a length of 70 cm from snout to tail.Sapheosaurus belongs to the clade Sapheosauridae, that also includes other taxa like Ankylosphenodon. It is believed to be was one of two aquatic sphenodont lineages, with Pleurosauridae being the other.