Palaeosaurus

Palaeosaurus (or Paleosaurus) is a genus of indeterminate archosaur known from two teeth found in the Bromsgrove Sandstone Formation and also either the Magnesian Conglomerate or the Avon Fissure Fill of Clifton, Bristol, England (originally Avon). It has had a convoluted taxonomic history. Richard Owen's mistake of associating prosauropod skeletal remains with the carnivorous teeth which Riley and Stutchbury called Palaeosaurus, combined with Friedrich von Huene's Teratosaurus minor, which was also a combination of carnivore and prosauropod remains, led paleontologists to view prosauropods as carnivorous animals for quite a long time. This error made it into several textbooks and other dinosaur reference works. In the autumn of 1834, surgeon Henry Riley (1797–1848) and the curator of the Bristol Institution, Samuel Stutchbury (15 January 1798 – 12 February 1859), began to excavate "saurian remains" at the quarry of Durdham Down, at Clifton, presently a part of Bristol, which is part of the Magnesian Conglomerate. In 1834 and 1835, they briefly reported on the finds. They provided their initial description in 1836, naming two new genera: Palaeosaurus and Thecodontosaurus. In 1836 Riley and Stutchbury briefly and informally published on two new fossil teeth (the holotype tooth of P. platyodon is listed under BRSMG *Ca7448/3 and the holotype tooth of P. cylindrodon is listed under BRSMG *Ca7449/4. Both are now listed under the latter species) found in or near the city of Bristol, England, which they called Palaeosaurus cylindrodon and Palaeosaurus platyodon. Riley and Stutchbury did not mean to assign these species to Saint-Hilaire's genus of teleosaurids; they simply did not know the name had been used. Thecodontosaurus was also named in this publication. Only in 1840 do Riley and Stutchbury fully describe their two species of Palaeosaurus, each based on a single sharp tooth from the Late Triassic Period. The spellings were then corrected to read Paleosaurus cylindrodon and Paleosaurus platyodon.