Upper Cretaceous, 67 - 65 mya
|Jaw of Dynamosaurus imperiosus|
Dynamosaurus is an extinct dinosaur known from a jaw fossil found in Montana's Hell Creek Formation. Dynamosaurus was describd by Henry Fairfield Osborn and Richard Swan Lull. It was related to Tyrannosaurus and Manospondylus.
Discovery and naming[change | change source]
The holotype of Tyrannosaurus rex, a partial skull and skeleton originally called AMNH 973 (AMNH stands for American Museum of Natural History), was discovered in the U.S. state of Montana in 1902 and excavated over the next three years. Another specimen (AMNH 5866), found in Wyoming in 1900, was described in the same paper under the name Dynamosaurus imperiosus. At the time of their initial description and naming, these specimens had not been fully prepared and the type specimen of T. rex had not even been fully recovered. In 1906, after further preparation and examination, Henry Fairfield Osborn recognized both skeletons as belonging to the same species. Because the name Tyrannosaurus rex had appeared just one page earlier than Dynamosaurus in Osborn's 1905 work, it was considered the older name and has been used since. Had it not been for page order, Dynamosaurus would have become the official name. Osborn did not synonymise the two genera.
Specimens[change | change source]
- AMNH 973 - a 13% complete skeleton famous for the jaw fossil currently housed in London, England
- The possible specimen RTMP 81.6.1 - otherwise known as Black Beauty. A possible well preserved skeleton.
References[change | change source]
- Osborn, H.F. (1905). "Tyrannosaurus and other Cretaceous carnivorous dinosaurs". Bulletin of the American Museum of Natural History 21 (3): 259–265. doi:10.1111/j.1468-5965.2007.00735_17.x. http://digitallibrary.amnh.org/dspace/handle/2246/1464.
- Osborn, H.F. 1906. Tyrannosaurus, Upper Cretaceous carnivorous dinosaur (second communication). 22: 281–296.