Ornithomimosauria

dinosaur

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Last updated

July 1, 2026

Quick Summary

Ornithomimosauria, meaning "bird mimic lizards," were a group of theropod dinosaurs that lived during the Cretaceous Period, approximately 125 to 66 million years ago. These dinosaurs, like the genus Ornithomimus, were characterized by their ostrich-like appearance, with long legs, toothless beaks, and often feathered bodies.1

Key features of Ornithomimosauria include:
* Appearance: Resembled modern ostriches, with long necks and legs adapted for running.1
* Diet: Likely omnivorous, though some members had beaklike jaws and lacked teeth.1
* Anatomy: Possessed three fingers of similar length and exceptionally long foot bones (metatarsals).1
* Diversity: The group includes various sizes, from small forms like Pelecanimimus to giants like Deinocheirus.1

Ornithomimosauria are classified within the Coelurosauria, a subgroup of theropod dinosaurs that also includes birds.2

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dinosaur
Tetanurae
Ornithomimids were medium-size to large theropods. Almost all of them were toothless, and apparently their jaws were covered by a horny beak; they also had very long legs and arms. A well-known example is Struthiomimus. Most were ostrich-sized and were adapted for fast running, with…
Read More
Ornithomimids were medium-size to large theropods. Almost all of them were toothless, and apparently their jaws were covered by a horny beak; they also had very long legs and arms. A well-known example is Struthiomimus. Most were ostrich-sized and were adapted for fast running, with…
Read More