What is "elsornis"

Elsornis is a genus of enantiornithine bird. Only one species is known, Elsornis keni. It lived during the Late Cretaceous. It is known from a partially articulated fossil skeleton found in the Gobi Desert in Mongolia.

The holotype fossil is given catalog number MPD - b 100/201. It is in the collection of the Mongolian Palaeontological Center. The fossil was collected at Togrogiin Shiree, South Gobi Aimak, Mongolia; Djadokhta Formation, Late Cretaceous, Campanian.

The fossil is extremely well preserved in three dimensions. It preserves a pneumatized Furcula, which was a character previously unknown in enantiornithines. Chiappe et al. (2007) conclude from the proportions of Elsornis ' pectoral skeleton that it was flightless or nearly so.