Himalayasaurus

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Himalayasaurus
Temporal range: Late Triassic, 215.56–212.0  Ma [1]
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Himalayasaurus.png
Life reconstruction of Himalayasaurus tibetensis
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Ichthyosauria
Family: Shastasauridae
Genus: Himalayasaurus
Dong, 1972
Type species
Himalayasaurus tibetensis
Dong, 1972

Himalayasaurus is an extinct genus of ichthyosaur from the Late Triassic Qulonggongba Formation of Tibet. The type species Himalayasaurus tibetensis was described in 1972 on the basis of fragmentary remains, including teeth, limb bones, and vertebrae. [2] The entire body length of Himalayasaurus is estimated to have been over 15 metres (49 ft) in length. [3] Himalayasaurus has since been considered a nomen dubium or "dubious name" because of the lack of features that set it apart from other ichthyosaurs, [4] although the presence of distinct cutting edges on its teeth have more recently been proposed as a unique feature of the genus (cutting edges have also been found in the ichthyosaur Thalattoarchon from the western United States). [5] Himalayasaurus belongs to the family Shastasauridae, which includes other large-bodied Triassic ichthyosaurs like Shonisaurus . [3]

See also

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References

  1. "†Himalayasaurus Dong 1972 (ichthyosaur)". Paleobiology Database. Fossilworks. Retrieved 11 August 2017.
  2. Dong, Z.-M. (1972). 珠穆朗玛峯地区的鱼龙化石[An ichthyosaur fossil from the Qomolangma (Mt. Everest) region]. In Young, C. C.; Dong, Z.-M. (eds.). 中国三迭纪水生爬行动物[Aquatic Reptiles from the Triassic of China]. Memoirs of the Institute of Vertebrate Paleontology and Paleoanthropology (in Chinese (China)). Vol. 9. pp. 7–10.
  3. 1 2 Motani, R.; Manabe, M.; Dong, Z.-M. (1999). "The status of Himalayasaurus tibetensis (Ichthyopterygia)" (PDF). Paludicola. 2 (2): 174–181. Archived from the original (PDF) on 2016-03-05. Retrieved 2013-01-07.
  4. Lucas, S.G.; González-León, C.M. (1995). "Ichthyosaurs from the Upper Triassic of Sonora and the biochronology of Triassic ichthyosaurs". Geological Society of America Special Papers. 301: 17–20.
  5. Fröbisch, N. B.; Fröbisch, J. R.; Sander, P. M.; Schmitz, L.; Rieppel, O. (2013). "Macropredatory ichthyosaur from the Middle Triassic and the origin of modern trophic networks". Proceedings of the National Academy of Sciences. 110 (4): 1393–1397. Bibcode:2013PNAS..110.1393F. doi: 10.1073/pnas.1216750110 . PMC   3557033 . PMID   23297200.