Zhongornis

Zhongornis (meaning "intermediate bird"[1]) is a genus of primitive avialan that lived during the Early Cretaceous. It was found in rocks of the Yixian Formation in Lingyuan City (China), and described by Gao et al. in 2008.[2]

Zhongornis has only one described species, Zhongornis haoae. The only specimen is a fossil slab and counterslab numbered D2455/6. It is in the collection of the Dalian Natural History Museum. It is a fairly complete skeleton about eight centimeters in length. Pores in the bones and unfused sutures in the skeleton indicate that the specimen was a juvenile, but the authors believe that it was developed enough to erect a new taxon on the basis of its unique morphological characters. There are feather impressions preserved on the right hand and also probable tail feathers preserved near the left foot. Zhongornis had a beaked mouth with no teeth. The tail is proportionately short, has thirteen vertebrae, and no pygostyle. The third finger has only two phalangeal bones, unlike non - avian dinosaurs and Confuciusornis, and more like Enantiornithes and more advanced avialans. These features and a cladistic analysis indicate that Zhongornis is the sister group to all pygostylia, meaning that it is intermediate between long - tailed Avialae like Archaeopteryx and more advanced taxa like Confuciusornis.