Linhenykus' hand does have a leftover bone for a second finger, but the nub of a digit wouldn't have worked at all, Xu added.
That makes Linhenykus the only known one-fingered dinosaur, he said.
The new dinosaur was discovered in a fossil-rich rock formation that dates to the late Cretaceous period, between 84 and 75 million years ago. The site is near the Inner Mongolian town of Linhe (map), which helped inspire the dinosaur's name.
Alvarezsauroid fossils have been found in North and South America as well as Asia, dating from the late Jurassic to the late Cretaceous. Finding an alvarezsauroid in Asia dated to the late Cretaceous adds to...