Imparavis attenboroughi Wang et al., 2024 (new genus and species)
(Type specimen of Imparavis attenboroughi [scale bar = 20 mm], from Wang et al., 2024)
Meaning of name: Imparavis = odd bird [in Latin]; attenboroughi = for Sir David Attenborough [British documentary presenter and conservationist]
Age: Early Cretaceous (Aptian), between 119–123 million years ago
Where found: Jiufotang Formation, Liaoning, China
How much is known: Nearly complete skeleton of one individual preserved with feather traces.
Notes: Imparavis was an enantiornithean, a group of bird-like, flying dinosaurs from the Cretaceous. Although they would have looked a lot like modern birds, most enantiornitheans had teeth. Imparavis was an exception in that regard, being one of the few known toothless enantiornitheans. Prior to its discovery, the only other enantiornitheans confirmed to have been toothless were the Late Cretaceous Gobipteryx and Gobipipus from Mongolia and Yuornis from China, making Imparavis one of the oldest known enantiornitheans to lack teeth. (The describers of Imparavis additionally reinterpret another enantiornithean from the Jiufotang Formation, Chiappeavis, as toothless as well.)
Imparavis may have spent time both in trees and on the ground, based on details of its hindlimb anatomy. Its wing bones exhibit pronounced muscle attachment points, suggesting that it might have been capable of rapid, powerful take-offs.
Reference: Wang, X., A.D. Clark, J.K. O'Connor, X. Zhang, X. Wang, X. Zheng, and Z. Zhou. 2024. First edentulous enantiornithine (Aves: Ornithothoraces) from the Lower Cretaceous Jehol avifauna. Cretaceous Research advance online publication. doi: 10.1016/j.cretres.2024.105867
