Arctosaurus

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Arctosaurus
Temporal range: Late Triassic, Carnian
Arctosaurus osborni.jpg
Sketch of the holotype
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: Archosauromorpha
Clade: Crocopoda
Clade: Allokotosauria
Genus: Arctosaurus
Adams, 1875
Type species
Arctosaurus osborni
Adams, 1875

Arctosaurus is an extinct genus of archosauromorph, possibly an allokotosaurian, [1] but was often classified as a sauropodomorph dinosaur between 1900 and 1976. Although it has also been classified as a theropod, recent review finds that the similarities it shares with theropods are spread throughout several groups of Late Triassic reptiles, and so it cannot be assigned any more specifically than to Archosauriformes. [2] Other authors have suggested trilophosaurian affinities. [3] [4] Based on the size of the vertebra, a size of about 1.5 metres (4.9 ft) in length is extrapolated.

Discovery and naming

It is based on holotype NMING: F14878, a neck vertebra that was found in 1859 by Captain Sherard Osborn on Cameron Island, Nunavut, Canada, in Late Triassic-age rocks of the Heiberg Formation. In 2016, the material of Arctosaurus osborni was redescribed. [1] The name Arctosaurus means "arctic lizard" in reference to the latitude where the holotype was discovered.

Related Research Articles

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Coelophysis is a genus of coelophysid theropod dinosaur that lived approximately 215 to 208.5 million years ago during the Late Triassic period from the middle to late Norian age in what is now the southwestern United States. Megapnosaurus was once considered to be a species within this genus, but this interpretation has been challenged since 2017 and the genus Megapnosaurus is now considered valid.

<span class="mw-page-title-main">Archosauromorpha</span> Infraclass of reptiles

Archosauromorpha is a clade of diapsid reptiles containing all reptiles more closely related to archosaurs rather than lepidosaurs. Archosauromorphs first appeared during the late Middle Permian or Late Permian, though they became much more common and diverse during the Triassic period.

<i>Tanystropheus</i> Extinct genus of reptiles

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<i>Azendohsaurus</i> Genus of herbivorous Triassic reptile

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<i>Lukousaurus</i> Extinct species of reptile

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<i>Poposaurus</i> Extinct genus of Archosaur

Poposaurus is an extinct genus of pseudosuchian archosaur from the Late Triassic of the southwestern United States. It belongs to the clade Poposauroidea, an unusual group of Triassic pseudosuchians that includes sail-backed, beaked, and aquatic forms. Fossils have been found in Wyoming, Utah, Arizona, and Texas. Except for the skull, most parts of the skeleton are known. The type species, P. gracilis, was described and named by Maurice Goldsmith Mehl in 1915. A second species, P. langstoni, was originally the type species of the genus Lythrosuchus. Since it was first described, Poposaurus has been variously classified as a dinosaur, a phytosaur, and a "rauisuchian".

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<span class="mw-page-title-main">Epipophyses</span> Bony projections of neck vertebrae in certain reptiles

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<span class="mw-page-title-main">Allokotosauria</span> Extinct clade of reptiles

Allokotosauria is a clade of early archosauromorph reptiles from the Middle to Late Triassic known from Asia, Africa, North America and Europe. Allokotosauria was first described and named when a new monophyletic grouping of specialized herbivorous archosauromorphs was recovered by Sterling J. Nesbitt, John J. Flynn, Adam C. Pritchard, J. Michael Parrish, Lovasoa Ranivoharimanana and André R. Wyss in 2015. The name Allokotosauria is derived from Greek meaning "strange reptiles" in reference to unexpected grouping of early archosauromorph with a high disparity of features typically associated with herbivory.

<span class="mw-page-title-main">Azendohsauridae</span> Extinct family of reptiles

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<i>Cryodrakon</i> Genus of large azhdarchid pterosaur from the Late Cretaceous

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References

  1. 1 2 Sues, Hans-Dieter (18 October 2016). "Arctosaurus osborni, a Late Triassic archosauromorph reptile from the Canadian Arctic Archipelago". Canadian Journal of Earth Sciences. 54 (2): 129–133. doi: 10.1139/cjes-2016-0159 .
  2. Nesbitt, Sterling J.; Irmis, Randall B.; Parker, William G. (2007). "A critical re-evaluation of the Late Triassic dinosaur taxa of North America". Journal of Systematic Palaeontology. 5 (2): 209–243. Bibcode:2007JSPal...5..209N. doi:10.1017/S1477201907002040. S2CID   28782207.
  3. Glut, D.F. (1997). "Excluded Genera". Dinosaurs: The Encyclopedia. McFarland & Company. pp. 1005–1010. ISBN   0-89950-917-7.
  4. Russell, Dale A. (1989). An Odyssey in Time: Dinosaurs of North America. Minocqua, Wisconsin: NorthWord Press, Inc. p. 26. ISBN   1-55971-038-1.