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32-750: 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

64-512: A fourth species is created, Palaeosaurus stricklandi ; these are now recognized to be those of a phytosaur . Von Huene, in 1908, recognized the tooth of Palaeosaurus platyodon belonged to a phytosaur and placed it into the new genus Rileya , forming the new combination Rileya platyodon . One of the holotype teeth of P. cylindrodon , presumably BRSMG *Ca7448/3, was destroyed during World War II , in 1940. The other tooth survives to this day. In 1959 German paleontologist Oskar Kuhn , for

96-655: Is around 500m thick and includes sandstones of both aeolian and fluviatile origin. The latter is between 400 and 600m thick and includes some siltstone and claystone beds. It overlies the varied lithologies of the Permian age Cumbrian Coastal Group . The Kirklinton Sandstone Formation in places overlies the Calder Sandstone Formation in the Carlisle and Vale of Eden basins of north and east Cumbria. A sandstone which underlies Sellafield and Drigg

128-640: Is early Triassic to Anisian in age and comprises variously coloured sandstones whose bases are frequently conglomeratic, together with mudstones and siltstones. The thickness of the formation is variable but reaches around 500m in the Worcester area. It is often encountered in older literature as the Lower Keuper Sandstone. The formation includes the Shepshed Sandstone Member. The Wildmoor Sandstone Formation (named from

160-758: Is known as the Sellafield Member and is assigned to the Helsby Sandstone Formation. The group is represented in Somerset and east Devon by the Otterton Sandstone and the underlying Budleigh Salterton Pebble Beds formations,. Rileyasuchus Rileyasuchus is a genus of phytosaur from the Rhaetian ( Late Triassic ) Magnesian Conglomerate of England . It has a confusing history, being associated with

192-408: 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

224-417: Is still followed today. Most of the skeletal bones ever assigned to Palaeosaurus cylindrodon and P. platyodon were also reassigned to Thecodontosaurus . The genera Rileya and Palaeosauriscus , as well as the species Palaeosaurus cylindrodon and Palaeosaurus platyodon , were all declared nomina dubia . In 2007, Peter Galton, reviewing the archosaurian fossils of the 1834 Bristol finds, reaffirmed

256-788: Is underlain by the Hawksmoor Formation (named from the Staffordshire locality of Hawksmoor) which includes the Hulme Member , a conglomerate and which is in turn underlain by the Huntley Formation (named from the Staffordshire locality of Huntley ). They are all of Scythian age. On the Cumbrian coast the Group comprises the Calder Sandstone Formation and the underlying St Bees Sandstone Formation. The former

288-682: The Antrim coast. The Group comprises different sequences in each of the various basins in which it is developed as described below. The sequence is most thickly developed in the Cheshire Basin , which also extends into north Shropshire. It comprises the following formations: The Helsby Sandstone Formation (named from the Cheshire village of Helsby where the type section is exposed at Helsby Hill ) comprises around 250m thickness of sandstone with conglomerate and siltstone which occurs across

320-633: The Thecodontosaurus bones that Owen assigned to the former genus. However, Huxley regarded P. cylindrodon as an unrelated carnivorous theropod . American paleontologist Edward Drinker Cope named a third species, Palaeosaurus fraserianus , in 1878, for an isolated tooth found in Triassic rocks in Pennsylvania . Today these are regarded as belonging to an indeterminate sauropodomorph dinosaur unrelated to Palaeosaurus . In 1881,

352-636: The Cheshire Basin. Older literature includes it as part of the Lower Keuper Sandstone. It is often divided into an upper Frodsham Member and a lower Delamere Member . Faulted blocks of these rocks are largely responsible for the prominent west facing escarpment of the Mid Cheshire Ridge and the Helsby Sandstone is exposed in numerous localities here, southwards from Runcorn through Frodsham to Utkinton , spectacularly at

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384-811: The Kidderminster Conglomerate Formation. Formerly known locally as the Polesworth Formation (from the Warwickshire village of Polesworth ), the Chester Formation here is of ?Olenekian to Anisian age. The Moira Formation (named from the Leicestershire village of Moira ) is of Induan/Olenekian age. Also encountered as the Hopwas or Moira Breccia. The Lenton Sandstone Formation (named from

416-680: The Midlands (though usually concealed) and notably in an outlier at Leek, Staffordshire . They extend south to the Severn Estuary and beyond there through Somerset to Budleigh Salterton on the coast of East Devon . There are further occurrences in Northern Ireland north and east of Limavady , east of Cookstown , between Dungannon and Armagh and along the Lagan Valley beneath Belfast and Newtownards and on

448-830: The Nottingham suburb of Lenton ) is of Induan/Olenekian age. The Stafford Basin includes the Kibbleston Formation (named from the Staffordshire locality of Kibbleston) which is underlain by the Wildmoor Formation which is in turn underlain by the Kidderminster Formation. The rock succession in the Needwood Basin includes the Hollington Formation (named from the Staffordshire locality of Hollington ) which

480-626: The Worcestershire locality of Wildmoor, north of Bromsgrove) is a 0 - 284m thick sequence of sandstones formerly known as the Upper Mottled Sandstone or Wildmoor Beds. It also includes some mudstones and siltstones. The Kidderminster Formation (named from the Worcestershire town of Kidderminster ) is a 0 - 200m thick sequence of conglomerates and sandstones previously known as either the Bunter Pebble Beds or

512-422: The bones assigned to Sellosaurus . He resurrected the genus Efraasia for some of these bones, to which he also assigned the bones that had been first described as Teratosaurus minor as well (although leaving out the teeth, which were recognized as non-dinosaurian). Like Galton in 1973, Yates's Efraasia also included the remains previously known as Palaeosaurus diagnosticus , although unlike Galton, Yates calls

544-507: The change in spelling, he changed the name back to Palaeosaurus , and this spelling was followed by all subsequent authors until 1959. Owen assigns other bones to Palaeosaurus , which would later be re-classified to the prosauropod dinosaur Thecodontosaurus . Contrary to Owen, in 1870, Thomas Henry Huxley described both Thecodontosaurus and Palaeosaurus as dinosaurs for the first time. He considered Palaeosaurus platyodon to be synonymous with Thecodontosaurus antiquus , most likely due to

576-445: The chimaeric nature of Palaeosaurus ; and Plateosauria , which included Thecodontosaurus and Plateosaurus , which had been described with the correct skulls, and therefore were correctly described as a herbivorous group. Thecodontosaurus was redescribed by a team of paleontologists led by Michael Benton in 2000, which placed Owen's mis-classified material under the genus Thecodontosaurus rather than Palaeosaurus , and this

608-645: The first time since 1840, recognized that the genus Palaeosaurus created by Riley and Stutchbury in 1836 was preoccupied and created the new generic name Palaeosauriscus to contain Palaeosaurus cylindrodon and all other species that had previously been described under Palaeosaurus . In 1964, Owen's mis-classified specimens caused American Edwin Harris Colbert to classify prosauropods into two groups – Palaeosauria, which included Palaeosaurus and Teratosaurus , thought to be carnivorous because of

640-442: The genus). It seems to have sat unrecognized for most of the 20th century, except for 1961 when Oskar Kuhn renamed it from Rileya to Rileyasuchus . Adrian Hunt in 1994 (doctoral dissertation) first suggested that it was a herrerasaurid , although this was never published. Benton et al. (2000) indicated that the type specimen was actually a chimera composed of a phytosaur humerus and Thecodontosaurus vertebrae. It

672-589: The highest coastal cliffs in northwest England at St Bees Head are formed in the St Bees Sandstone, the lowermost formation within the group. In the northeast they extend from Hartlepool south through the Vale of Mowbray and the Vale of York , then south through Nottinghamshire into the English Midlands, though are very largely concealed by superficial sediments. They occur widely through

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704-651: The identification of the two teeth and humeri of Palaeosaurus platyodon ( Rileya ) as belonging to a phytosaur, and regarded P. cylindrodon ( Palaeosauriscus ) as an indeterminate archosaur. He agreed with Benton that Rileya is dubious, but suggested that Palaeosauriscus may be valid, based on its now-destroyed tooth with a "subcircular cross-section and fine, obliquely inclined denticles". In 1932, Von Huene assigned new material to Palaeosaurus ; numerous prosauropod bones found in Germany. Because of Owen's Thecodontosaurus bones misassigned to Palaeosaurus cylindrodon ,

736-638: 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 . In 1842, Sir Richard Owen created the name Dinosauria . In the same publication, he attempted to redescribe Riley and Stutchbury's Paleosaurus and Thecodontosaurus , which he did not consider to be dinosaurs. Not knowing of

768-555: The outlier of Beeston Castle hill and lastly within the Peckforton Hills . The Wilmslow Sandstone Formation (named from the town of Wilmslow in Cheshire) comprises up to 900m thickness of early Triassic sandstones with occasional siltstones. It was earlier known as the Upper Mottled Sandstone. In Wirral , the 60m thick Thurstaston Sandstone Member and the 2m thick Thurstaston Hard Sandstone Bed are distinguished at

800-411: 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

832-447: The species Efraasia minor , synonymizing both species. E. minor was claimed to have priority because von Huene described Teratosaurus minor several pages before Palaeosaurus diagnosticus in his 1908 publication. The name minor therefore would take precedence over diagnostica for this species. Type species : " Palaeosaurus " cylindrodon ( nomen dubium ) Riley and Stutchbury 1836 (an indeterminate archosauromorph later renamed

864-461: The species was thought to be a prosauropod. Von Huene therefore referred his new species to Palaeosaurus , creating the name P. diagnostica . In 1973, Peter Galton , a British paleontologist, moved the species into its own genus, creating the new combination Efraasia diagnosticus . For several decades, most scientists considered Efraasia a junior synonym of Sellosaurus ; however, in 2003 Adam Yates , another British palaeontologist, redescribed

896-485: The taxonomy of Palaeosaurus and Thecodontosaurus , and being a replacement name for a preoccupied genus ( Rileya , which had already been used by Ashmead, and Howard both in 1888 for a hymenopteran ). Friedrich von Huene named the new genus for two vertebrae and a humerus from deposits in Bristol . He had recognized it as a phytosaur by 1908 (by which point a few Palaeosaurus species had been added to

928-538: The top of the sequence. The Chester Formation (named from the city of Chester ) comprises sandstones with some conglomerates and siltstones of early Triassic age. It ranges from less than 90m to over 220m in thickness. It has been known in the past as the Bunter Pebble Beds and the Chester Pebble Beds Formation. There are a couple of reference sections for this sequence in the vicinity of Chester. The Kinnerton Sandstone Formation (named from

960-689: The twin villages of Higher and Lower Kinnerton on the England/Wales border west of Chester) is a sequence which ranges from 0m to over 150m thickness of largely aeolian sandstones of early Triassic age. It was formerly known as the Lower Mottled Sandstone. Once known locally as the Bromsgrove Sandstone Formation (from the town of Bromsgrove in Worcestershire), the Helsby Sandstone Formation

992-533: The type species of Palaeosauriscus cylindrodon , as Palaeosaurus was pre-occupied) Other species: [REDACTED] [REDACTED] Bromsgrove Sandstone Formation These rocks are found in northwest England as far north as Carlisle (and extending just into Scotland around Annan and Gretna ) and in the Vale of Eden and then extending down the Cumbrian coast into Lancashire and Cheshire . They are mostly obscured by superficial deposits but

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1024-505: 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

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