Struthiomimus (Ostrich mimic)
Struthiomimus (Ostrich mimic)
Named By : Henry Fairfield Osborn - 1917
Diet : Omnivore
Size : Estimated 4.3 meters long
Type of Dinosaur : Sauropod
Type Species : S. altus (type), S. sedens
Found in : Canada, Alberta - Dinosaur Park Formation and Horseshoe Canyon Formation. USA - Hell Creek Formation
When it Lived : Late Cretaceous, 76-74 million years ago
Struthiomimus (meaning “ostrich mimic”, from the Greek stroutheios/stroutheios meaning “of the ostrich” and mimos/mimos meaning “mimic” or “imitator”) is a genus of ornithomimid dinosaurs from the late Cretaceous of North America. Ornithomimids were bipedal, long-legged and ostrich-like dinosaurs that had teethless beaks. The species of the type, Struthiomimus altus, is one of the most common small dinosaurs within Dinosaur Provincial Park; its number of specimens suggests that the animals were herbivores and omnivores rather than pure carnivores.
In the year 1901, Lawrence Lambe found some insufficient remains, holotype CMR 930. He identified them as Ornithomimus altus. He placed them within the same genus as materials previously mentioned by Othniel Charles Marsh in 1890. Altus is the specific name that comes originated from Latin that means “lofty” or “noble”. In 1914, a complete Skeleton (AMNH 5339) was found in the hands of Barnum Brown on the Red Deer River site in Alberta which led to O. altus to be classified as the “type” subgenus of a brand new genus called Struthiomimus in the work of Henry Fairfield Osborn in 1917. Dale Russell made Struthiomimus a full Genus in 1972, while in addition to noting several other specimens belonging to it. AMNH 5375 AMNH 5385 AMNH 5421 CMN 897 CMN 9902, and ROM 1790. all skeletons that were partially complete. The species of type, S. altus, is identified from various skulls and skeletons. In 1916, Osborn changed the name of Ornithomimus tenuis Marsh 1890 as Struthiomimus tenuis. It is now considered to be as a nomen dubium. In the year 2016, ROM 1790 was made the holotype for a brand new species and genus, Rativates evadens.
In later years William Arthur Parks named four different varieties that belong to Struthiomimus: Struthiomimus brevetertius Parks 1926, Struthiomimus samueli Parks 1928, Struthiomimus currellii Parks 1933 and Struthiomimus ingens Parks 1933. These are currently thought of as either Dromiceiomimus-related or Ornithomimus.
In 1997, Donald Glut mentioned the name Struthiomimus lonzeensis. It was likely the lapsus calami that was which is a misnomer for Ornithomimus Lonzeensis (Dollo 1903) Kuhn 1965. Struthiomimus altus is from the Late Campanian (Judithian age) Oldman Formation.
A second possible type of Struthiomimus is identified as early Maastrichtian (Edmontonian period) Horseshoe Canyon Formation. Since dinosaur fauna exhibits rapid turnover, it’s probable that the younger Struthiomimus specimens are different in S. altus even though there is no name given to them.
Additional Struthiomimus samples from earlier Lance Formation and equivalents are larger (similar to Gallimimus in size) and be more straight and have longer hand claws as seen in Ornithomimus. A fairly complet Lance Formation specimen, BHI 1266, was first identified as Ornithomimus Sedens (named in 1892) by Marsh in the year 1892) and was later designated by Marsh in 1892). It was later classified as Struthiomimus sedens. One 2015 paper by van der Reest et al. identified BHI 1266 in the form of Ornithomimus sp. Another paper from in the same year analyzed this specimen as Struthiomimus sp. in the absence of a revision for both genera.