Jianchangosaurus, new therizinosaur from Early Cretaceous of China

[Ben Creisler <bcreisler@gmail.com>]

From: Ben Creisler
bcreisler@gmail.com


New in PLoS ONE:

Hanyong Pu, Yoshitsugu Kobayashi, Junchang Lü, Li Xu, Yanhua Wu, Huali
Chang, Jiming Zhang & Songhai Jia (2013)
An Unusual Basal Therizinosaur Dinosaur with an Ornithischian Dental
Arrangement from Northeastern China.
PLoS ONE 8(5): e63423.
doi:10.1371/journal.pone.0063423
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0063423


Therizinosauria are an unusual group of theropod dinosaurs, found
mostly in the Cretaceous deposits in Mongolia, China and western USA.
The basal forms of this group are represented by incomplete or
disarticulated material. Here, we report a nearly complete,
articulated skeleton of a new basal therizinosaur from the Early
Cretaceous Yixian Formation of Jianchang County, western part of
Liaoning Province, which sheds light on our understanding of anatomy
of basal therizinosaurs. This new dinosaur shows some typical
therizinosaur features, such as neural spines of the anterior caudal
vertebrae that possess anterior and posterior alae, a rectangular
buttress on the ventrolateral side of the proximal end of metacarpal
I, and appressed metatarsal shafts. Our phylogenetic analysis suggests
that it is a basal therizinosaur (sister taxon to Therizinosauroidea)
because it bears many basal therizinosaur characters in the dentition,
pelvis and hind limbs. The new therizinosaur described here has unique
tooth and jaw characters such as the offsetting of the tooth row by a
shelf and dentary teeth with labially concave and lingually convex
dentary teeth, similar to ornithopods and ceratopsians.