New Alvarezsaurs: Xiyunykus & Bannykus

[ZoPteryx]

Open Access Paper!
https://www.cell.com/current-biology/fulltext/S0960-9822(18)30987-4


Preserved elements in gray.

Xiyunykus pengi ("Peng's Western Claw") and Bannykus wulatensis ("Wulatehouqi Half Claw") are two basal alvarezsaurs from the Early Cretaceous of China that help demonstrate the transition of the group's forelimbs from the typical coelurosaurian form to the specialized nearly monodactyl limbs of derived members.

https://phys.org/news/2018-08-rare-intermediate-fossils-insight-evolution.html

[ceratopsian]

Interesting article. Thanks for posting - I hadn't picked this one up elsewhere.

[Vidusaurus]

I think the transition in skull morphology from basal to derived is just as interesting as the forelimb transition. Look at the head on Xiyunykus - it wouldn't look out of place on a Compsognathid or other basal coelurosaur.