The National Academy of Sciences unveiled today a newly discovered fossil of a very peculiar lizard. The fossil reveals that the ancient tree living lizard coasted through the air using a wing-like membrane stretched across elongated ribs.
The gliding lizard lived about 150 million years ago during the Early Cretaceous period. The specimen, detailed in the March 19 issue of the journal for the Proceedings of the National Academy of Sciences, is about 6 inches long, and appeared to have died at a young age.
The fossil, described by Xing Xu of Shenyang Normal University in China and his colleagues, was discovered in the Liaoning Province in northeastern China. Over the last several years, many other very unique fossils have been discovered in the same region. Everything from feathered dinosaurs to some the world's earliest birds.
The gliding lizard, currently being named Xianglong zhaoi, had a gliding membrane, called a patagium.The patagium stretched across eight elongated dorsal ribs. Fully expanded, the layer of stretchy skin would have spanned about 4.5 inches across.
Xianglong zhaoi also had curved claws that would have allowed it to dwell in treetops, from which it could launch into the air. Once airborne, the little lizard could probably glide farther than modern flying lizards, perhaps as far as 50 yards at a time, Xu said.
Most gliding animals, such as “flying” squirrels and frogs, use a membrane spread between their toes or between their body and legs to stay airborne. A gliding membrane spread between elongated ribs is only known to occur in an ancient lizard-like animal that lived during the Late Triassic era and certain lizards currently living in Southeast Asia.
“It is really amazing to see evolution making nearly identical structures in animals of different origins spanning such a long history,” said Xu.