Dianchungosaurus

Last updated

Dianchungosaurus
Temporal range: Early Jurassic,
195.5–189.6  Ma
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: Archosauria
Clade: Pseudosuchia
Clade: Crocodylomorpha
Clade: Crocodyliformes
Genus: Dianchungosaurus
Young, 1982
Species:
D. lufengensis
Binomial name
Dianchungosaurus lufengensis
Young, 1982
Synonyms
  • Dianchungosaurus elegans Zhao, 1986
  • Tianchungosaurus Young, 1982

Dianchungosaurus (meaning "Dianchung lizard" [1] ) is an extinct genus of mesoeucrocodylian crocodyliform from the Early Jurassic of China. It was previously considered a dinosaur, but it was recently reclassified as a mesoeucrocodylian by Paul Barrett and Xing Xu (2005). [2] It is probably the same animal as the informally named "Tianchungosaurus". [1] The type species is D. lufengensis and it was described in 1982. [1] A second species, D. elegans, was named in 1986, [3] but it has since become a synonym of the type species. [2]

Contents

Material

Two specimens were originally referred to this taxon: [1]

Both remains come from the Lower Lufeng Formation, near Dianchung, in the Yunnan Province in China. The age of the material is thus Sinemurian (Early Jurassic). [2]

Systematics

Originally classified by Young in 1982 in Heterodontosauridae, [1] Dianchungosaurus lufengensis' affinities were doubted by some, who regarded it as a nomen dubium, but it was until recently usually considered a valid heterodontosaurid. In 2005, a paper by Barrett and Xu focused on this problematic taxon and found its specimens to form an hypodigm, a chimera of different animals. The holotype, IVPP V4735a, was reclassified as a mesoeucrocodylian, while the paratype, IVPP V4735b, was found to be an indeterminate sauropodomorph. [2]

To maintain the stability in the literature, the holotype retains the name D. lufengensis, while the paratype awaits a formal description. [2]

References

  1. 1 2 3 4 5 C.-C. Young. (1982). [On a new genus of dinosaur from Lufeng, Yunnan]. Selected Works of Yang Zhungjian. Science Press, Beijing 38-42
  2. 1 2 3 4 5 Barrett, P.M.; Xu X. (2005). "Reassessment of Dianchungosaurus lufengensis Yang, 1982, an enigmatic reptile from the Lower Lufeng Formation (Lower Jurassic) of Yunnan Province, People's Republic of China". Journal of Paleontology. 79 (5): 981–986. doi:10.1666/0022-3360(2005)079[0981:ARODLY]2.0.CO;2. S2CID   89542580.
  3. Zhao, (1986). The Cretaceous biota of China: Reptilia. in Hao, Su, Yu, Li, Li, Wang, Qi, Guan, Hu, Liu, Yang, Ye, Shou and Zang (eds.). The Cretaceous System of China. Stratigraphy of China. 12, 67-73, plates XI, XII.