Yixianosaurus

Yixianosaurus (meaning "Yixian lizard") was a maniraptoran dinosaur genus from the Early Cretaceous (Aptian stage, 122 million years ago) of China. It is known only from a pair of fossilized arms complete with fossilized feathers. Its exact placement within Maniraptora is uncertain, though its hands resemble those of another feathered dinosaur, Epidendrosaurus.[1]

The type species, Yixianosaurus longimanus, was formally described by Xu X. & Wang Xiao-lin in 2003. The partial skeleton was recovered in Liaoning, in northeastern China.

Classification
The describers considered the exact placement of Yixianosaurus within Maniraptora to be uncertain, but because the hand length resembled that of another feathered dinosaur, Epidendrosaurus (now Scansoriopteryx), they suggested it was a close relative of the Scansoriopterygidae. Other researchers have suggested the specimen may have come from a dromaeosaurid. Subsequent analyses were divided on whether is it is more primitive and outside the clade Eumaniraptora &ndahs; this would mean that advanced characteristics such as the long hands and short arms evolved independently in this species[4] – or a basal member of the more advanced Paraves. Xu et al. (2013) concluded that the presence of large pennaceous feathers on parts of the forelimb strongly supports that Yixianosaurus was adapted for limited aerial locomotion.