Outline: a typical theropod
Xiyunykus
"western claw"
- Lived
- 137 to 133 million years ago, Early Cretaceous
- Diet
- Carnivore
- Group
- Theropods
- Found in
- China
- Named by
- Xu et al. 2018
Where its fossils were found
The evidence
Today
135 million years ago
Field notes
About Xiyunykus
What it was like
Xiyunykus was an early alvarezsaur, a small, bird-like theropod. It is known from parts of the skull and skeleton. Its features are halfway between early members of the group and later ones with one big claw on each short arm.
Its world
It lived about 137 to 133 million years ago, in the Early Cretaceous, in what is now northwestern China. Its bones come from the Shengjinkou Formation, where the sauropods Silutitan and Hamititan also lived.
How it was found
Xu and colleagues named it in 2018, at the same time as Bannykus.
Lived alongside
Found in the same rock formations
Close relatives
Other members of Alvarezsauroidea
Sources: WikidataNamed in: X. Xu, J. Choiniere, and Q.-W. Tan, R. B. J. Benson, J. Clark, C. Sullivan, Q. Zhao, F.-L. Han, Q.-Y. Ma, Y.-M. He, S. Wang, H. Xing, L. Tan. 2018. Two early Cretaceous fossils document transitional stages in alvarezsaurian dinosaur evolution. Current Biology 28:2853-2860