Yuornis

Yuornis is one of the most complete Late Cretaceous enantiornithine birds ever found, with a three-dimensionally preserved skull.1

Unlike most enantiornithines, Yuornis had no teeth. Its skull looked a lot like modern birds because it lost several bones, like the lacrimal and postorbital.1

The name Yuornis comes from 'Yu', the one-character abbreviation for Henan province in China, where it was discovered.1

Yuornis lived about 72 to 66 million years ago, during the very end of the Age of Dinosaurs.3

Its closest relative might be Gobipteryx, another toothless bird from the Late Cretaceous, but scientists are not sure because tooth loss evolved many times.1