Ornithomimosauria
Saurischia Theropoda Tetanurae Coelurosauria Ornithomimosauria [?]
Named by Barsbold, 1976, lightly built cursorial theropods, up to 5 meter long, with long, slender hindlimbs, small skull and a long neck. Defined as al bullatosaurs closer to Ornithomimus than to Troodon by Holtz in 1994.
Barsbold, 1976a, Diagnosis: Moderately large theropods with a small skull, elongated toothless jaws, equipped with a horny beak, with a capsular basisphenoid and parabasal canals. The palatal complex is of the reptilian type. The anterior limbs are not reduced, relatively weakly developed, with a non-pulley type wrist and hand of the non-grasping type. All three metacarpal elements are approximately equal, the claw phalanges of the hand are more or less straight.
The ilium is elongated in a different way, the pubis has a small “shoe-like” thickening, the ischium has a proximally displaced elongation, the proximal compression of its third elements is varied, the foot structure is three or four toed. 4 Composition: Family Ornithomimidae Marsh, 1890, Garudimimidae Barsbold, fam. nov. Comparison: According to size, the ornithomimosaurs are approximately equal or somewhat larger than the “small” theropods, in one case the Mongolian specimen reached the dimensions of a tyrannosaurid (Osmolska et al., 1972). The basisphenoidal capsule is perforated posteriorly by a large opening, while in the saurornithoidids (Coelorosauria), the second group with such a capsule (Barsbold, 1974), it is of the closed type.
Parabasal canals among theropods were first found in the ornithomimosaurs and are connected with the development of the basisphenoidal capsule, that allows the presence of similar canals also in the saurornithoidids. The unreduced anterior limbs are characterized by a narrow humerus and antebrachium, that is a weak development of the deltopectoral crest and the ulnar join, which is also common to the Deinocheirids (Osmolska and Roniewicz, 1970) as opposed to other theropods with unreduced front limbs. The roughly equal metacarpal elements are found also in the deinocheirids, among other theropods the first element is usually highly reduced in length. The non-pulley type wrist joint was also characteristic to the non-grasping hand in the tyrannosaurids and supposedly in the deinocheirids (Barsbold, 1976c).
The ornithomimosaural pelvis in general is similar to that of the carnosaurs (allosaurids, tyrannosaurids), but it is considerably smaller in size as well as mass. The distal “shoe-like” thickening of the pubis is considerably less than in the named groups. The wide amplitude of diversions in the structure of the foot in the ornithomimosaurs—the degree of the elongation of the metatarsus and the 5 proximal compression of its third element, is observed in various theropods, but usually does not reach such a significant dimension inside a single group, most clearly illustrated by the loss of the first toe of the foot. The ventral flattening of the unguals of the foot is perceived as a distinguishing peculiarity of the ornithomimosaurs. Distribution: Cretaceous, North America, Central Asia
Cretaceous Early
Spain
Pelecanimimus polyodon - Las Hoyas Konservat-lagerstatte
US
Coelosaurus
Coelosaurus affinis - Arundel Formation, Maryland
Australia
Timimus hermani - Otway Group, Dinosaur Cove, Victoria
China
Beishanlong grandis - Xinminpu Group
Hexing qingyinn - Yixian Formation, Liaoning
Shenzhousaurus orientalis - Yixian Formation, Liaoning
Mongolia
Harpymimus okladnikovi - Shinekhudukskaya Svita
Thailand
Kinnareemimus khonkaenensis - Sao Khua Formation
Cretaceous Late
The Netherlands
Megalosaurus bredai (1) - Maastricht Beds
Canada
Dromiceiomimus
Dromiceiomimus brevitertius - Horseshoe Canyon Formation, Alberta
Dromiceiomimus samueli - Judith River Group (Wedge), Alberta
Struthiomimus brevitertius - Edmonton Group, Alberta
Struthiomimus ingens - Edmonton Group, Alberta
Struthiomimus samueli - Oldman Formation, Alberta
Ornithomimus
Ornithomimus edmontonensis - Judith River Group (Wedge), Horseshoe Canyon Formation, Alberta
Struthiomimus curreli - Edmonton Group, Alberta
Struthiomimus
Ornithomimus altus - Judith River Group (Wedge), Horseshoe Canyon Formation, Alberta
Struthiomimus altus - Judith River Group (Wedge), Horseshoe Canyon Formation, Alberta
US
Coelosaurus
Coelosaurus antiquus - Black Creek Formation, North Carolina, Moorville Chalk, Alabama, New Egypt Formation, Navesink Formation, Mount Laural Formation, Wenonah Formation, New Jersey, Severn Formation, Maryland
Ornithomimus
Ornithomimus velox - Denver Formation, Colorado, Kaiparowits Formation, Utah
Ornithomimus antiquus ? - Severn Formation, Maryland
Dryptosaurus antiquus - Severn Formation, Maryland
Struthiomimus antiquus - Severn Formation, Maryland
Ornithomimus sedens - Lance Formation, Wyoming
Ornithomimus tenuis - Judith River Formation (Wedge), Montana
China
Archaeornithomimus
Archaeornithomimus asiaticus - Iren Dabasu Formation
Ornithomimus asiaticus - Iren Dabasu Formation
Qiupalong henanensis - Quiba Formation
Sinornithomimus dongi - Ulansuhai Formation
Mongolia
Anserimimus planinychus - Nemegt Formation
Gallimimus bullatus - Nemegt Formation
Gallimimus mongoliensis - Baynshirenskaya Svita
Garudimimus brevipes - Baynshirenskaya Svita
Uzbekistan
Archaeornithomimus
Archaeornithomimus bissektensis - Bissekt Formation
Nomen Nudem: \\\"Ginnareemimus\\\"; Orcomimus; Sanchusaurus