Ornithomimosauria

Ornithomimosaurs Temporal range: Cretaceous, 140–66 Ma[1] PreꞒ Ꞓ O S D C P T J K Pg N
Collection of seven ornithomimosaurs, clockwise from top left: Gallimimus, Anserimimus, Ornithomimus, Deinocheirus, Harpymimus, Struthiomimus and "Gallimimus mongoliensis"
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Dinosauria
Clade:	Saurischia
Clade:	Theropoda
Clade:	Maniraptoriformes
Clade:	†Ornithomimosauria Barsbold, 1976
Subgroups[9]
†Aviatyrannis?[2] †Haplocheirus? †Nedcolbertia[3] †Nqwebasaurus?[4][5] †Thecocoelurus? †Valdoraptor? †Macrocheiriformes Cuesta et al., 2021[6] †Harpymimus †Pelecanimimus †Shenzhousaurus †Ornithomimoidea Marsh, 1890[7] †Arkansaurus †Hexing[8] †Kinnareemimus[1] †Deinocheiridae †Ornithomimidae
Synonyms
Deinocheirosauria Barsbold, 1976 Arctometatarsalia Holtz, 1994

Ornithomimosauria ("bird-mimic lizards") are theropod dinosaurs which bore a superficial resemblance to the modern-day ostrich. They were fast, omnivorous or herbivorous dinosaurs from the Cretaceous Period of Laurasia (now Asia, Europe and North America), as well as possibly Africa.^[10][5] The group first appeared in the Early Cretaceous and persisted until the Late Cretaceous. Primitive members of the group include Nqwebasaurus, Pelecanimimus, Shenzhousaurus, Hexing and Deinocheirus, the arms of which reached 2.4 m (8 feet) in length. More advanced species, members of the family Ornithomimidae, include Gallimimus, Struthiomimus, and Ornithomimus. Some paleontologists, like Paul Sereno, consider the enigmatic alvarezsaurids to be close relatives of the ornithomimosaurs and place them together in the superfamily Ornithomimoidea (see classification below).