Jixiangornis

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Jixiangornis
Fossil range: Early Cretaceous

Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Jeholornithiformes?
Family:	Jeholornithidae?
Genus:	Jixiangornis Q. Ji, S. Ji, H. Zhang, You, J. Zhang, L. Wang, Yuan & X. Ji, 2002
Species:	J. orientalis

Binomial name

Jixiangornis orientalis
Q. Ji, S. Ji, H. Zhang, You, J. Zhang, L. Wang, Yuan & X. Ji, 2002

Jixiangornis is the name given to a genus of basal bird from the Early Cretaceous. Like later birds, it had developed a beak, but it had a long tail, unlike modern birds. Since teeth were still present in some more advanced short-tailed birds, Jixiangornis seems to have evolved its beak independently of modern birds. The long forelimb (131% of hindlimb length) indicates a flying bird. Jixiangornis is currently known only from the type specimen, a complete skeleton. The fossil was found in the Yixian Formation near Beipiao City, western Liaoning, China.

The type and presently only species, J. orientalis ("Oriental bird from the Yixian Formation"), was described in November 2002. Ji et al (2002) considered Jixiangornis capable of stronger flight than either Archaeopteryx or Shenzhouraptor. Their phylogenetic tree shows Jixiangornis forming a clade ("Euavialae" of Ji et al.) with short-tailed birds that excludes Archaeopteryx and Shenzhouraptor.

An alternative view was presented by Zhou Zong-He and Zhang Fu-Cheng in 2006. They classified both Jixiangornis and Shenzhouraptor as junior synonyms of Jeholornis prima, meaning that Jixiangornis cannot be more advanced than Shenzhouraptor. This approach, however, seems problematical given the numerous differences between Jixiangornis and Shenzhouraptor/Jeholornis.

[edit] See also

Yixianornis grabaui, a more advanced bird

[edit] References

Ji, Q.; Ji, S.; Zhang, H.; You, H.; Zhang, J.; Wang, L.; Yuan, C. & Ji, X. (2002): A new avialan bird - Jixiangornis orientalis gen. et sp. nov. - from the Lower Cretaceous of Western Liaoning, NE China. Journal of Nanjing University (Natural Sciences) 38(6): 723-736 [in Chinese with English abstract].
Zhou, Z.-H. & Zhang, F.-C. (2006): Mesozoic birds of China - A synoptic review. Vertebrata Palasiatica 44(1): 74-98. PDF fulltext