Sunjiagou Formation

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Sunjiagou Formation
Stratigraphic range: Late Wuchiapingian-earliest Induan
Type Geological formation
Unit of Shiqianfeng Group
Underlies Liujiagou Formation
Overlies Shangshihezi Formation
Thickness100-200 metres
Lithology
Primary Sandstone, Siltstone, Mudstone
Location
CountryFlag of the People's Republic of China.svg  China
Extent Shanxi

The Sunjiagou Formation is a geological formation in Shanxi, China. It is of Lopingian age. The lower and middle parts of the formation consists of intensely bioturbated fine grained sandstones and thinly interbedded mudstones, deposited in a shallow-shore lake depositional environment, while the upper part consists of fine grained sandstone, siltstone and mudstone. [1] Alongside the Naobaogou Formation, it has provided an important vertebrate fauna.

Paleobiota

GenusSpeciesMaterialNotes
Sanchuansaurus [2] S. pygmaeus Pareiasaur
Shihtienfenia [2] S. permicaPareiasaur
Shihtienfenia-Paleozoological Museum of China.jpg
Seroherpeton [3] S. yangquanensisright upper jaw and palate Embolomeri
Seroherpeton.png
Taoheodon [4] T. baizhijuni Dicynodont
Cryptodontia [5] IndeterminatePartial skullDicynodont

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Sanchuansaurus is an extinct genus of pareiasaur from the late Permian Sunjiagou Formation of China. The genus contains a single species, S. pygmaeus, known from a partial maxilla and left leg bones. A 2013 study suggested that both Sanchuansaurus and another Chinese pareiasaur, Huanghesaurus, were synonymous with Shansisaurus. However, this has not been followed in future research, with later papers considering Sanchuansaurus to be distinct, with Huanghesaurus and Shansisaurus possibly being synonymous with Shihtienfenia, another Chinese pareiasaur.

References

  1. Chu, Daoliang; Tong, Jinnan; Song, Haijun; Benton, Michael J.; Bottjer, David J.; Song, Huyue; Tian, Li (2015-06-09). "Early Triassic wrinkle structures on land: stressed environments and oases for life". Scientific Reports. 5 (1): 10109. doi: 10.1038/srep10109 . ISSN   2045-2322. PMC   4460569 . PMID   26054731.
  2. 1 2 Benton, Michael J. (August 2016). "The Chinese pareiasaurs". Zoological Journal of the Linnean Society. 177 (4): 813–853. doi:10.1111/zoj.12389. hdl: 1983/6d1a4f9b-a768-4b86-acb1-b3ad1f7ee885 .
  3. Chen, Jianye; Liu, Jun (2020-12-01). "The youngest occurrence of embolomeres (Tetrapoda: Anthracosauria) from the Sunjiagou Formation (Lopingian, Permian) of North China". Fossil Record. 23 (2): 205–213. doi: 10.5194/fr-23-205-2020 . ISSN   2193-0066.
  4. Liu, Jun (2020-01-02). "Taoheodon baizhijuni , gen. et sp. nov. (Anomodontia, Dicynodontoidea), from the upper Permian Sunjiagou Formation of China and its implications". Journal of Vertebrate Paleontology. 40 (1): e1762088. doi:10.1080/02724634.2020.1762088. ISSN   0272-4634. S2CID   221749476.
  5. Yi J, Liu J, 2020. Pareiasaur and dicynodont fossils from upper Permian of Shouyang, Shanxi, China. Vertebrata PalAsiatica, 58(1): 16–23