Sinosauropteryx

Sinosauropteryx (meaning "Chinese reptilian wing", in Chinese 中华龙鸟: zhonghua longniao) was the first genus of dinosaur outside of Avialae (birds and their immediate relatives) to be found with evidence of feathers. They were covered with "furry" coats of very simple filament-like feathers. Structures that indicate colouration have been preserved for some of the feathers, which also makes Sinosauropteryx the first non-avialian dinosaurs where colouration has been determined. Colouration includes a banded tail with reddish and light bands. Some contention has arisen with an alternative interpretation of the filamentous impression as remains of collagen fibres.

Sinosauropteryx were small theropods with unusually long tails and short arms. They were close relatives of the similar but older genus Compsognathus, both genera belonging to the family Compsognathidae. Only one species of Sinosauropteryx has been named: S. prima, meaning "first" in reference to its status as the first feathered non-avialian dinosaur species discovered. A handful of specimens have been described. One specimen previously assigned to this genus represents either a second, as-yet unnamed species or a related genus.

Sinosauropteryx prima lived in what is now northeastern China during the early Cretaceous period. They were among the first dinosaurs discovered from the Yixian Formation in Liaoning Province, and were members of the remarkable Jehol Biota. Well-preserved fossils of this species illustrate many aspects of their biology, such as their diet and reproduction.