flying dragon lizard
Xianglong (meaning "flying lizard" in Chinese) is a genus of Cretaceous lizard discovered in the Liaoning Province of China. It is known from LPM 000666, a single complete skeleton with skin impressions. The specimen comes from the Barremian-age Lower Cretaceous Yixian Formation, near Yizhou. The most notable feature about Xianlong is its bizarre oversized ribs, eight on each side, which were attached to a membrane and allowed the lizard to glide. It was an acrodont lizard, and a cladistic analysis indicates it was grouped with iguanians such as agamines, chamaeleonids, and leiolepidines.
The fossil specimen found was 15.5 centimeters (6.1 in) long, 9.5 centimeters (3.7 in) of which was tail, but the describers say it was a juvenile. So far this is the only known fossil gliding lizard, though there are other unrelated animals that also use their ribs to glide.