Eoenantiornis

Eoenantiornis is a genus of enantiornithean birds which lived during the early Cretaceous period (124.6 Ma ago). It is known from a single fossil specimen found in the Yixian Formation in Liaoning province, China.

Eoenantiornis Temporal range: Early Cretaceous,
Holotype specimen, Paleozoological Museum of China
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Dinosauria
Clade:	Saurischia
Clade:	Theropoda
Clade:	Avialae
Clade:	†Enantiornithes
Order:	†Eoenantiornithiformes Hou et al., 1999
Family:	†Eoenantiornithidae Hou et al., 1999
Genus:	†Eoenantiornis Hou et al., 1999
Species:	†E. buhleri
Binomial name
†Eoenantiornis buhleri Hou et al., 1999

In 1999, the type species Eoenantiornis buhleri was named and described by Hou Lianhu, Larry Martin, Zhou Zhonghe and John Alan Feduccia. The generic name combines a Greek ἠώς, èos, "dawn" with Enantiornis, in reference to a presumed more basal position in relation to that genus. The specific name honours the late German paleornithologist Paul Bühler.[1]

Fossil

The holotype, IVPP V11537, was found at Heitizigou in Liaoning in a layer of the lower Yixian Formation dating from the early Aptian. It consists of a nearly complete and articulated skeleton with skull compressed on a plate, preserving most of the feather integument.[1] It represents a not fully grown individual.[2]

In 2005, Eoenantiornis was completely redescribed.[2]

Originally, the species was placed in a "family" Eoenantiornithidae and even an "order" Eoenantiornithiformes.[1] In 2005, these concepts were abandoned and it was concluded that the position was in the clade Euenantiornithes. It is one of the oldest known derived enantiornithines.[2]