Priodontognathus Temporal range: Upper Jurassic, | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | † Ornithischia |
Clade: | † Thyreophora |
Suborder: | † Ankylosauria |
Genus: | † Priodontognathus Seeley, 1875 |
Species: | †P. phillipsii |
Binomial name | |
†Priodontognathus phillipsii (Seeley, 1869) | |
Synonyms | |
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Priodontognathus (meaning "saw tooth jaw") was a genus of ankylosaurian dinosaur possibly from the Oxfordian-age Upper Jurassic Lower Calcareous Grit of Yorkshire, England. It is a dubious genus based on a maxilla, and has been erroneously mixed up with iguanodonts and stegosaurs.
English paleontologist Harry Govier Seeley, who described the genus, first mentioned the holotype (SMC B53408), a maxilla or upper jaw bone, in 1869. [1] Seeley was at the time compiling a catalogue of the fossils of the Woodwardian Museum. Part of these formed the Forbes Collection that after the death of James Forbes-Young had in 1862 been donated to the University of Cambridge by his sons Charles Young and Henry Young. The provenance of this particular bone from that collection was unknown; first believed to be found near Tilgate from a Lower Cretaceous stratum, it was later thought to have been discovered somewhere near the coast of Yorkshire in a Jurassic layer. [2] Seeley initially assumed that it was referable to Iguanodon , and named it Iguanodon Phillipsii. The specific name honoured geology professor John Phillips. The five inch long fragment lacked the teeth, only seventeen empty tooth sockets being visible. By 1875, after subsequent preparation had uncovered the replacement teeth within the jaw bone, Seeley had recognized that it was different, and so gave it the generic name Priodontognathus. The name is derived from Greek prion, "saw", odous, "tooth" and gnathos, "jaw", in recognition of the form of its teeth. [3] Because the replacement teeth had not yet erupted, their serrations had not been worn down and many sharp denticula could be seen, shaped as the points of a saw.
Because armored dinosaurs were very poorly known at the time, he had little to compare it to, and in light of this it is not too surprising that he later, in 1893, had it mixed up with the stegosaurian Omosaurus (now Dacentrurus ); [2] stegosaurs are most closely related to the ankylosaurs within the Thyreophora. At this time, he named a species Omosaurus phillipsii based on a femur (YM 498), but also provisionally equated this species to Priodontognathus phillipsii, despite the two species being based on non-comparable material. [2] This was extremely confusing as both shared the same specific name (see at the bottom). It led to a later misunderstanding by some authors, assuming Omosaurus phillipsii was nothing but Priodontognathus phillipsii reassigned to Omosaurus. However, this is precluded by the mere fact that both species have been based on different type specimens.
After this time, Priodontognathus was generally considered to be a stegosaurid, [4] [5] although at least one author, Baron Franz Nopcsa, recognized that it was not, and assigned it to "Acanthopholididae", which we would recognize as Nodosauridae. [6] Alfred Sherwood Romer also recognized that it was an ankylosaurian, although he synonymized it with Hylaeosaurus . [7]
Peter Galton reassessed the genus in 1980 and established that it was a distinct genus, which he compared to Priconodon and Sauropelta and assigned to Nodosauridae. [8] While his assessment of it as a type of ankylosaurian has been accepted, his belief that it was valid was not, and it has been usually considered a dubious genus of uncertain ankylosaurian affinities since then. [9] [10] [11] [12]
As mentioned, Seeley named a femur Omosaurus phillipsii in 1893, which has become confused with this animal, due to being discussed in the same article (and considered to possibly be the same genus), and due to them having the same specific name. Omosaurus phillipsii, now known as "Dacentrurus" phillipsii or "Omosaurus" phillipsii (depending on how an author denotes dubious species), is a dubious species of stegosaurian from the Malton Oolite Member of the Corallian Oolite Formation, Slingsby, North Yorkshire. [2] Galton (1983) found it to have no diagnostic features, and that its major significance was of being the only record then known of Oxfordian stegosaurians. [13] The femur, which is in three pieces, is that of a juvenile. [13]
As an ankylosaurian, Priodontognathus would have been a slow quadrupedal herbivore, built low to the ground, and possessing armor as a protective feature against theropods and other carnivores. [12] It was a rather small animal, a few metres long; if the Oxfordian date is correct this might be seen as a feature shared with all early nodosaurids.
The double "i" at the end of the specific name for both Priodontognathus and "Omosaurus" phillipsii is an old formulation and is today not done. The extra "i" has not been formally removed and is the only valid spelling under the International Code of Zoological Nomenclature, but authors sometimes leave it off. For that matter, as mentioned above regarding the name of "Omosaurus" phillipsi, Priodontognathus will sometimes be referred to as "Iguanodon" phillipsii. [9] [11] [12] Seeley's original use of a capital to write Phillipsii is now no longer conventional, lower case being used for the beginning of all specific epithets even if they were derived from personal names, resulting in this case in a phillipsi.
Ankylosauria is a group of herbivorous dinosaurs of the clade Ornithischia. It includes the great majority of dinosaurs with armor in the form of bony osteoderms, similar to turtles. Ankylosaurs were bulky quadrupeds, with short, powerful limbs. They are known to have first appeared in the Middle Jurassic, and persisted until the end of the Cretaceous Period. The two main families of Ankylosaurs, Nodosauridae and Ankylosauridae are primarily known from the Northern Hemisphere, but the more basal Parankylosauria are known from southern Gondwana during the Cretaceous.
Cryptosaurus is a dubious genus of dinosaur known from a partial femur from the Late Jurassic of England. The sole species is Cryptosaurus eumerus.
Acanthopholis is a genus of ankylosaurian dinosaur in the family Nodosauridae that lived during the Late Cretaceous Period of England. A single species, A. horrida, exists.
Dacentrurus, originally known as Omosaurus, is a genus of stegosaurian dinosaur from the Late Jurassic to Early Cretaceous of Europe. Its type species, Omosaurus armatus, was named in 1875, based on a skeleton found in a clay pit in the Kimmeridge Clay in Swindon, England. In 1902 the genus was renamed Dacentrurus because the name Omosaurus had already been used for a crocodylian. After 1875, half a dozen other species would be named but perhaps only Dacentrurus armatus is valid. Finds of this animal have been limited and much of its appearance is uncertain. It was a heavily built quadrupedal herbivore, adorned with plates and spikes, reaching 8–9 metres (26–30 ft) in length and 5 metric tons in body mass.
Lexovisaurus is a genus of stegosaur from mid-to-Late Jurassic Europe, 165.7-164.7 mya. Fossils of limb bones and armor fragments have been found in middle to late Jurassic-aged strata of England and France.
Ankylosauridae is a family of armored dinosaurs within Ankylosauria, and is the sister group to Nodosauridae. The oldest known Ankylosaurids date to around 122 million years ago and went extinct 66 million years ago during the Cretaceous–Paleogene extinction event. These animals were mainly herbivorous and were obligate quadrupeds, with leaf-shaped teeth and robust, scute-covered bodies. Ankylosaurids possess a distinctly domed and short snout, wedge-shaped osteoderms on their skull, scutes along their torso, and a tail club.
Nodosauridae is a family of ankylosaurian dinosaurs, from the Late Jurassic to the Late Cretaceous period in what is now North America, South America, Europe, and Asia.
Anoplosaurus is an extinct genus of herbivorous nodosaurid dinosaur, from the late Albian-age Lower Cretaceous Cambridge Greensand of Cambridgeshire, England. It has in the past been classified with either the armored dinosaurs or the ornithopods, but current thought has been in agreement with the "armored dinosaur" interpretation, placing it in the Ankylosauria.
Sarcolestes is an extinct genus of ankylosaurian ornithischian dinosaur from the Oxford Clay of England. The current type and only species is S. leedsi, and the holotype is a single partial left mandible. The genus and species were named in 1893 by Richard Lydekker, who thought they belonged to a theropod.
Syngonosaurus is an extinct genus of ornithopod dinosaur from the Early Cretaceous. It was an iguanodontian discovered in England and was first described in 1879. The type species, S. macrocercus, was described by British paleontologist Harry Seeley in 1879 and it was later synonymised with Acanthopholis, but the genus was reinstated in a 2020 study, when Syngonosaurus and Eucercosaurus were reinterpreted as basal iguanodontians.
Texasetes is a genus of ankylosaurian dinosaurs from the late Lower Cretaceous of North America. This poorly known genus has been recovered from the Paw Paw Formation near Haslet, Tarrant County, Texas, which has also produced the nodosaurid ankylosaur Pawpawsaurus.
Hoplitosaurus was a genus of armored dinosaur related to Polacanthus. It was named from a partial skeleton found in the ?Barremian-age Lower Cretaceous Lakota Formation of Custer County, South Dakota. It is an obscure genus which has been subject to some misinterpretation of its damaged remains. Although there was a push to synonymize it with Polacanthus in the late 1980s-early 1990s, Hoplitosaurus has been accepted as a valid albeit poorly known genus in more recent reviews.
Stegosauria is a group of herbivorous ornithischian dinosaurs that lived during the Jurassic and early Cretaceous periods. Stegosaurian fossils have been found mostly in the Northern Hemisphere, predominantly in what is now North America, Europe, Africa, South America and Asia. Their geographical origins are unclear; the earliest unequivocal stegosaurian, Huayangosaurus taibaii, lived in China.
Palaeoscincus is a dubious genus of ankylosaurian dinosaur based on teeth from the mid-late Campanian-age Upper Cretaceous Judith River Formation of Montana. Like several other dinosaur genera named by Joseph Leidy, it is an historically important genus with a convoluted taxonomy that has been all but abandoned by modern dinosaur paleontologists. Because of its wide use in the early 20th century, it was somewhat well known to the general public, often through illustrations of an animal with the armor of Edmontonia and the tail club of an ankylosaurid.
Dracopelta is a monospecific genus of ankylosaur dinosaur from Portugal that lived during the Late Jurassic in what is now the Lourinhã Formation. The type and only species is Dracopelta zbyszewskii, which is represented by a partial skeleton including unpublished material.
Priconodon is an extinct genus of dinosaur, known from its large teeth. Its remains have been found in the Aptian-Albian age Lower Cretaceous Arundel Formation of Muirkirk, Prince George's County, Maryland, USA and the Potomac Group, also located in Maryland.
Genasauria is a clade of extinct beaked, primarily herbivorous dinosaurs. Paleontologist Paul Sereno first named Genasauria in 1986. The name Genasauria is derived from the Latin word gena meaning ‘cheek’ and the Greek word saúra (σαύρα) meaning ‘lizard.’ It is hypothesized that Genasauria had diverged from Lesothosaurus by the Early Jurassic. Cranial features that characterize Genasauria include a medial offset of the maxillary dentition, a sprout-shaped mandibular symphysis, moderately sized coronoid process, and an edentulous anterior portion of the premaxilla. A distinguishing postcranial feature of Genasauria is a pubic peduncle of the ilium that is less robust than the ischial peduncle. Genasauria is commonly divided into Neornithischia and Thyreophora. Neornithischia is characterized by asymmetrical distributions of enamel covering the crowns of the cheek teeth, an open acetabulum, and a laterally protruding ischial peduncle of the ilium. Neornithischia includes ornithopods, pachycephalosaurs, and ceratopsians. Thyreophora is characterized by body armor and includes stegosaurs, ankylosaurs, Scelidosaurus, and Scutellosaurus.
This timeline of stegosaur research is a chronological listing of events in the history of paleontology focused on the stegosaurs, the iconic plate-backed, spike-tailed herbivorous eurypod dinosaurs that predominated during the Jurassic period. The first scientifically documented stegosaur remains were recovered from Early Cretaceous strata in England during the mid-19th century. However, they would not be recognized as a distinct group of dinosaurs until Othniel Charles Marsh described the new genus and species Stegosaurus armatus in 1877, which he regarded as the founding member of the Stegosauria. This new taxon originally included all armored dinosaurs. It was not until 1927 that Alfred Sherwood Romer implemented the modern use of the name Stegosauria as specifically pertaining to the plate-backed and spike-tailed dinosaurs.
This timeline of ankylosaur research is a chronological listing of events in the history of paleontology focused on the ankylosaurs, quadrupedal herbivorous dinosaurs who were protected by a covering bony plates and spikes and sometimes by a clubbed tail. Although formally trained scientists did not begin documenting ankylosaur fossils until the early 19th century, Native Americans had a long history of contact with these remains, which were generally interpreted through a mythological lens. The Delaware people have stories about smoking the bones of ancient monsters in a magic ritual to have wishes granted and ankylosaur fossils are among the local fossils that may have been used like this. The Native Americans of the modern southwestern United States tell stories about an armored monster named Yeitso that may have been influenced by local ankylosaur fossils. Likewise, ankylosaur remains are among the dinosaur bones found along the Red Deer River of Alberta, Canada where the Piegan people believe that the Grandfather of the Buffalo once lived.