Genus: Coniornis MARSH, 1893
Etymology: Greek Konis “dust, chalk [Cretaceous]” and Greek ornis for bird. “Cretaceous Bird”

Species: altus MARSH, 1893

Holotype: YPM 515

Locality: 1 mile above the mouth of Dog Creek, near the mouth of the Judith River, Fergus County, Montana.

Horizon: Judith River Formation.


Age: Judithian age, Campanian Stage, Senonian subepoch, Upper Gulf epoch, Late Cretaceous.

Material: Right tibia missing distal end.

Referred material:

= Hesperornis montana SHUFELDT, 1915

Holotype: USNM 8199

Locality: 1 mile above mouth of Dog Creek, Fergus County, Montana.

Horizon: Claggett Formation.


Age: Campanian Stage, Senonian Subepoch, Gulf Epoch, Late Cretaceous.

Material: 23rd dorsal vertebra.