Ichthyornis is an extinct genus of toothy seabird-like ornithuran from the Late Cretaceous of North America. Its fossil remains are known from the chalks of Alberta, Alabama, Kansas, New Mexico, Saskatchewan, and Texas, in strata that were laid down in the Western Interior Seaway, spanning from the Cenomanian to the Campanian ages of the Late Cretaceous. Ichthyornis is a common component of the Niobrara Formation fauna, and numerous specimens have been found.