Cathayornis
Encyclopedia
Cathayornis is a genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of enantiornithine bird from the Jiufotang Formation
Jiufotang Formation
The Jiufotang Formation is an Early Cretaceous geological formation in Chaoyang, Liaoning which has yielded fossils of feathered dinosaurs, primitive birds, pterosaurs, and other organisms. . It is a member of the Jehol group. The exact age of the Jiufotang has been debated for years, with...

 of Liaoning
Liaoning
' is a province of the People's Republic of China, located in the northeast of the country. Its one-character abbreviation is "辽" , a name taken from the Liao River that flows through the province. "Níng" means "peace"...

, People's Republic of China
People's Republic of China
China , officially the People's Republic of China , is the most populous country in the world, with over 1.3 billion citizens. Located in East Asia, the country covers approximately 9.6 million square kilometres...

 and, in the case of the possible species C. chabuensis, from the Jingchuan Formation of Inner Mongolia
Inner Mongolia
Inner Mongolia is an autonomous region of the People's Republic of China, located in the northern region of the country. Inner Mongolia shares an international border with the countries of Mongolia and the Russian Federation...

.

Description and species

Zhou and Hou (2001) distinguished Cathayornis from the similar Sinornis by the former's larger size, a shorter, straighter, finger number I, with a slightly longer claw (ungual
Ungual
An ungual is a highly modified distal toe bone which ends in a hoof, claw, or nail. Elephants and other ungulates have ungual phalanges, as did the sauropods and horned dinosaurs. A claw is a highly modified ungual phalange.As an adjective, ungual means related to nail, as in periungual .-External...

), the absence of an atitrochanter, and other features. The type and possibly only species is Cathayornis yandica.

Other species – C. aberransis, C. chabuensis and C. caudatus – have been described, but their assignment to the same genus as C. yandica has never been thoroughly tested.

Classification

Paul Sereno
Paul Sereno
Paul Callistus Sereno is an American paleontologist from the University of Chicago who discovered several new dinosaur species on several continents. He has conducted excavations at sites as varied as Inner Mongolia, Argentina, Morocco, and Niger...

 et al., in 2002, considered Cathayornis a junior synonym of Sinornis. They interpreted the anatomies of the two as very similar and sharing key autapomorphies of the pygostyle.

The first thorough review of Sinornis and Cathayornis was published by Jingmai O'Connor and Gareth Dyke in 2010. O'Connor and Dyke concluded that despite the 2001 paper by Sereno and colleagues, the two birds were not synonyms and in fact differ in several clear ways, including different proportions in the wing claws and digits, differences in the pelvis, and size of the pygostyle.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK