Parasaurus

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Parasaurus
Temporal range: Wuchiapingian, 258.9–255.7 Ma
Restoration
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: Parareptilia
Order: Procolophonomorpha
Clade: Pareiasauria
Family: Pareiasauridae
Genus: Parasaurus
von Meyer, 1857
Type species
Parasaurus geinitzi
von Meyer, 1857

Parasaurus (meaning "near lizard") is a genus of pareiasaur known from fossils collected in the Kupferschiefer in Germany (Hesse, Thuringia and Lower Saxony), dating to the Late Permian (Wuchiapingian). The type species, Parasaurus geinitzi, described by Hermann von Meyer in 1857,[1] was the first pareiasaur ever described.[2] The seven known specimens were redescribed in 2008.[2]

Discovery and naming[edit]

As early as 1848, pareiasaur fossils have been reported from Germany;[3] some of these fossils may have belonged to Parasaurus.[4] It was not until 1857 when von Meyer described these fossils and created the Parasaurus genus.[1] von Meyer classified Parasaurus as a reptile but it was classified as a pareiasaur when the family was created in 1888.[5][4] Lee (1997) classified Parasaurus as a nomen dubium. In 2008, Tsuji and Müller re-evaluated the genus.[2]

Description[edit]

Parasaurus was small for a pareiasaur, only around 50 centimetres (1.6 ft) long. Axial osteoderms appear to be absent. The skull surface is pitted, with small spike-like horns on the supratemporal and quadratojugal.[2]

Phylogeny[edit]

Below is a cladogram from Tsuji et al. (2013):[6]

Pareiasauria

Paleoenvironment[edit]

The Kupferschiefer is a marine unit that forms part of the Zechstein, a sequence of rocks formed on the edge of the Zechstein Sea, a large inland shallow sea that existed in Northern Europe during the Late Permian. The environment at the time of deposition is considered to have been semi-arid. The terrestrial flora of the Zechstein is dominated by conifers, with seed ferns also being common, while taeniopterids, ginkgophytes and sphenophytes are rare. Other terrestrial vertebrates found in the Kupferschiefer and lower Zechstein include the gliding weigeltisaurid reptiles Weigeltisaurus and Glaurung, the archosauromorph reptile Protorosaurus, the cynodont Procynosuchus, and indeterminate captorhinids, dicynodonts, and dissorophid temnospondyls.[7][8][9][10]

References[edit]

  1. ^ a b Meyer, H.V. (1857). Beiträge zur näheren Kenntnis fossiler Reptilien. Neues Jahrbuch für Mineralogie, Geognosie, Geologie und Petrefaktenkunde, 1857: 103–104.
  2. ^ a b c d L. A. Tsuji and J. Müller. (2008). A Re-evaluation of Parasaurus geinitzi, the first named pareiasaur (Amniota, Parareptilia). Canadian Journal of Earth Sciences 45(10):1111-1121
  3. ^ Geinitz, H.B. (1848). Die Versteinerungen des deutschen Zechsteingebirges. In Die Verteinerungen des Zechsteingebirges und Rothliegenden oder des permischen Systemes in Sachsen. Edited by H.B. Geinitz and A. von Gutbier. Arnoldische Buchhandlung, Dresden and Leipzig, pp. 1–29. Google Scholar
  4. ^ a b Society of Vertebrate Paleontology (24 June 2013). "Pareiasaur: Bumpy beast was a desert dweller". ScienceDaily. Retrieved 17 May 2014.
  5. ^ H. G. Seeley. (1888). Croonian Lecture: Researches on the Structure, Organization, and Classification of the Fossil Reptilia. II. On Pareiasaurus bombidens (Owen), and the Significance of Its Affinities to Amphibians, Reptiles, and Mammals. Philosophical Transactions of the Royal Society of London B 179:59-109
  6. ^ Tsuji, L. A.; Sidor, C. A.; Steyer, J. - S. B.; Smith, R. M. H.; Tabor, N. J.; Ide, O. (2013). "The vertebrate fauna of the Upper Permian of Niger—VII. Cranial anatomy and relationships of Bunostegos akokanensis (Pareiasauria)". Journal of Vertebrate Paleontology. 33 (4): 747–763. doi:10.1080/02724634.2013.739537. S2CID 86097405.
  7. ^ Bernardi, Massimo; Petti, Fabio Massimo; Kustatscher, Evelyn; Franz, Matthias; Hartkopf-Fröder, Christoph; Labandeira, Conrad C.; Wappler, Torsten; Van Konijnenburg-Van Cittert, Johanna H.A.; Peecook, Brandon R.; Angielczyk, Kenneth D. (2017-12-01). "Late Permian (Lopingian) terrestrial ecosystems: A global comparison with new data from the low-latitude Bletterbach Biota". Earth-Science Reviews. 175: 18–43. Bibcode:2017ESRv..175...18B. doi:10.1016/j.earscirev.2017.10.002. ISSN 0012-8252. S2CID 134260553.
  8. ^ Witzmann, Florian (2005-05-31). "A dissorophid temnospondyl in the Upper Permian Kupferschiefer of Germany". Neues Jahrbuch für Geologie und Paläontologie - Monatshefte. 2005 (5): 289–300. doi:10.1127/njgpm/2005/2005/289. ISSN 0028-3630.
  9. ^ Sues, Hans-Dieter; Munk, Wolfgang (March 1996). "A remarkable assemblage of terrestrial tetrapods from the Zechstein (Upper Permian: Tatarian) near Korbach (northwestern Hesse)". Paläontologische Zeitschrift. 70 (1–2): 213–223. doi:10.1007/BF02988279. ISSN 0031-0220. S2CID 128465809.
  10. ^ Bulanov, V. V.; Sennikov, A. G. (2015-12-01). "Glaurung schneideri gen. et sp. nov., a new weigeltisaurid (Reptilia) from the Kupferschiefer (Upper Permian) of Germany". Paleontological Journal. 49 (12): 1353–1364. doi:10.1134/S0031030115120035. ISSN 1555-6174. S2CID 87461613.