[D] Ornithomimus [Su] [sG]
Cretaceous Late Campanian Maastrichtian
Saurischia Theropoda Tetanurae Coelurosauria Ornithomimosauria Ornithomimidae
Genus - Skull
Ornithomimus (Marsh ,1890) > Ornithomimus velox (Marsh, 1890) > Ornithomimus edmontonensis (Sternberg, 1933) >> Struthiomimus curreli (Parks, 1933)
The first ornithomimosaur remains consisted of the imperfect foot of a dinosaur which was discovered in 1889 by George Cannon in Late Cretaceous rocks near Denver, Colorado. Marsh described this material in 1890 as Ornithomimus velox (\\\\\\\"speedy bird mimic\\\\\\\") and, in addition named two other species Ornithomimus tenuis (a partial foot and hindlimb) and \\\\\\\"Ornithomimus\\\\\\\" grandis from other fragmentary remains.
Both of the latter had been discovered by J.B. Hatcher in Montana, in the later 1880\\\\\\\'s. More fragmentary material was described by Marsh in 1892 (Ornithomimus sedens and Ornithomimus minutus) and he recognised from the remains of the pelvis of Ornithomimus sedens that these animals were not ornithopods as originally suspected, but theropods of a hitherto unknown sort.
In 1902 Lawrence Lambe described another specimen from the Late Cretaceous of Red Deer River, Alberta as Ornithomimus altus; this was again rather fragmentary comprising hindlimbs, feet and pelvic bones.
It was not until 1917 that the first reasonably complete skeleton of an ornithomimosaur was described by Henry Fairfield Osborn. This skeleton consisted of a more-or-less completely preserved animal, lacking only parts of the head, some of the vertebrae and a few limb bones.
It allowed the first accurate skeletal reconstruction to be drawn. on the basis of this fine specimen, Osborn proposed that it was virtually indistinguishable from Lambe\\\\\\\'s Ornithomimus altus but suggested that a new generic name Struthiomimus (\\\\\\\"ostrich mimic\\\\\\\") altus be used. osborn claimed that Struthiomimus was from a geologically earlier period than Ornithomimus and also differed in that Struthiomimus still had a small splint-like remnant of a fourth toe on its hindfoot which Ornithomimus lacked.
The more complete of the two species assigned to Ornithomimus is Ornithomimus edmontonensis. It has a length of the presacral vertebral column that is somewhat less than that of the hindlimb. The scapula is shorter than the humerus. The antebrachium is slender.