Ichthyornis Temporal range: Late Cretaceous,93–83.5 Ma |
|
---|---|
Cast skeleton, Rocky Mountain Dinosaur Resource Center | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Genus: |
†Ichthyornis Marsh, 1873 |
Species: | †I. dispar |
Binomial name | |
Ichthyornis dispar (Marsh, 1872) |
|
Synonyms | |
Angelinornis Kashin 1972 Species synonymy
|
Angelinornis Kashin 1972
Colonosaurus Marsh, 1872c
Plegadornis Wetmore 1962 (preoccupied)
Ichthyornis (meaning "fish bird", after its fish-like vertebrae) was a genus of toothed seabird-like avialan from the late Cretaceous period 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 during the Turonian through Campanian ages, about 95-83.5 million years ago. Ichthyornis is a common component of the Niobrara Formation fauna, and numerous specimens have been found.
Ichthyornis has been historically important in shedding light on bird evolution. It was the first known prehistoric bird relative preserved with teeth, and Charles Darwin noted its significance during the early years of the theory of evolution. Ichthyornis remains important today as it is one of the few Mesozoic era ornithurans known from more than a few specimens.
It is thought that Ichthyornis was the Cretaceous ecological equivalent of modern seabirds such as gulls, petrels, and skimmers. An average specimen was the size of a pigeon, 24 centimetres (9.4 in) long, with a skeletal wingspan (not taking feathers into account) of around 43 centimetres (17 in), though there is considerable size variation among known specimens, with some smaller and some much larger than the type specimen of I. dispar.