Changyuraptor yangi was a gliding predator which lived in the Cretaceous period in what is now Liaoning, China.
Its remarkable tail feathers – measuring up to 30cm – are the longest in any non-avian dinosaur.
This unusual plumage helped the creature to slow down during flight and land safely.
C. yangi is a new species of microraptorine, a group related to early avians.
These ancient creatures offer clues to the origin of flight – and the transition from feathered dinosaurs to birds.
Palaeontologists once thought that four-winged gliders were a stepping stone in the path to two-winged flight.
But recent fossil discoveries suggest that microraptorines were an evolutionary side-branch.