Yikezhaogia

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Yikezhaogia
Temporal range: Early Triassic
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Synapsida
Clade: Therapsida
Clade: Therocephalia
Superfamily: Baurioidea
Genus: Yikezhaogia
Li, 1984
Type species
Yikezhaogia megafenestrala
Li, 1984

Yikezhaogia is an extinct genus of therocephalian therapsids from the Early Triassic of Inner Mongolia (China). [1] [2] It is known from a single fragmentary skull and associated postcranial bones representing the species Yikezhaogia megafenestrala. It is identifiable as a therocephalian by its thin postorbital bar behind the eye socket, its elongated temporal opening behind the bar, and a thin lower jaw with a low coronoid process. Large tooth sockets in the upper jaw indicate that Yikezhaogia had large caniniform teeth. The teeth of the lower jaw are blunt-tipped and cylindrical. [3] Although its exact position among therocephalians is uncertain, Yikezhaogia is probably a basal member of the group Baurioidea. [2]

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References

  1. Li, Yuhe (1984). "On a New Scaloposaurid from Inner Mongolia" (PDF). Vertebrata PalAsiatica. 22 (1): 21–28.
  2. 1 2 Abdala, F.; Rubidge, B. S.; Van Den Heever, J. (2008). "The Oldest Therocephalians (Therapsida, Eutheriodontia) and the Early Diversification of Therapsida". Palaeontology. 51 (4): 1011. doi: 10.1111/j.1475-4983.2008.00784.x .
  3. Sun, A. (1991). "A review of Chinese therocephalian reptiles" (PDF). Vertebrata PalAsiatica. 29 (2): 85–94.