Guanlong wucaii (was RE: Early Version of T. Rex Is Discovered)

[Tim Williams <twilliams_alpha@hotmail.com>]

Tom Holtz wrote:


> Paper, and News & Views, should be out within the next hour or so.

Yep, indeed it is...

Xing Xu, James M. Clark, Catherine A. Forster, Mark A. Norell, Gregory M. 
Erickson, David A. Eberth, Chengkai Jia and Qi Zhao. (2006).  A basal 
tyrannosauroid dinosaur from the Late Jurassic of China.  Nature 439: 
715-718

Abstract: The tyrannosauroid fossil record is mainly restricted to 
Cretaceous sediments of Laurasia, although some very fragmentary Jurassic 
specimens have been referred to this group.  Here we report a new basal 
tyrannosauroid, _Guanlong wucaii_ gen. et sp. nov., from the lower Upper 
Jurassic of the Junggar Basin, northwestern China.  _G. wucaii_ is the 
oldest known tyrannosauroid and shows several unexpectedly primitive pelvic 
features.  Nevertheless, the limbs of _G. wucaii_ share several features 
with derived coelurosaurs, and it possesses features shared by other 
coelurosaurian clades.  This unusual combination of character states 
provides an insight into the poorly known early radiation of the 
Coelurosauria.  Notably, the presumed predatory _Guanlong_ has a large, 
fragile and highly pneumatic cranial crest that is among the most elaborate 
known in any non-avian dinosaur and could be comparable to some classical 
exaggerated ornamental traits among vertebrates.

Theropoda Marsh, 1881

Coelurosauria von Huene, 1914

Tyrannosauroidea Osborn, 1905

_Guanlong wucaii_ gen. et sp. nov.

Etymology. The generic name is derived from the Chinese Guan (crown) and 
long (dragon); the specific name is from the Chinese wucai (five colours), 
which refers to the rich colours of rocks that produced the specimens.

Holotype. IVPP (Institute of Vertebrate Paleontology and Paleoanthropology, 
Beijing) V14531 is a partly articulated skeleton preserving most of the 
elements.

Referred material. IVPP V14532 is much smaller than the holotype and is a 
fully articulated, nearly complete skeleton.

Locality and horizon. Wucaiwan area, Junggar Basin, Xinjiang; Oxfordian 
upper part of the Shishugou Formation.