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1" Tyrannosaur (Daspletosaurus?) Juvenile Tooth | Two Medicine Formation | Montana

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Original price $295.00 - Original price $295.00
Original price
$295.00 - $295.00
Current price $295.00
Juvenile Daspletosaurus horneri (sp?)

Late Cretaceous (~70 Million Years)

Pondera County, Montana

Two Medicine Formation

1" (25.4 mm)
Daspletosaurus (/dæsˌpliːtəˈsɔːrəs/ das-PLEET-o-SAWR-əs; meaning "frightful lizard") is a genus of tyrannosaurid dinosaur that lived in Laramidia between about 79.5 and 74 million years ago, during the Late Cretaceous Period. The genus Daspletosaurus contains two species. Fossils of the earlier type species, D. torosus, have been found in Alberta, while fossils of the later second species, D. horneri, have been found only in Montana. A possible third species, also from Alberta, awaits formal identification and another possible species D. degrootorum, also exists, but it may belong to the separate genus Thanatotheristes instead. Daspletosaurus is closely related to the much larger and more recent tyrannosaurid Tyrannosaurus rex. Like most tyrannosaurids, Daspletosaurus was a multi-tonne bipedal predator equipped with dozens of large, sharp teeth. Daspletosaurus had the small forelimbs typical of tyrannosaurids, although they were proportionately longer than in other genera.

As an apex predator, Daspletosaurus was at the top of the food chain, probably preying on large dinosaurs like the ceratopsid Centrosaurus and the hadrosaur Hypacrosaurus. In some areas, Daspletosaurus coexisted with another tyrannosaurid, Gorgosaurus, though there is some evidence of niche differentiation between the two. While Daspletosaurus fossils are not as common than other tyrannosaurid fossils, the available specimens allow some analysis of the biology of these animals, including social behavior, diet and life history.
The Two Medicine Formation is a geological formation, or rock body, in northwestern Montana and southern Alberta that was deposited between 83.5 ± 0.7 million years ago and 70.6 ± 3.4 million years ago, during Campanian (Late Cretaceous) time. It crops out to the east of the Rocky Mountain Overthrust Belt, and the western portion (about 2,000 feet thick) of this formation is folded and faulted while the eastern part, which thins out into the Sweetgrass Arch, is mostly undeformed plains. Below the formation are the nearshore (beach and tidal zone) deposits of the Virgelle Sandstone, and above it is the marine Bearpaw Shale. Throughout the Campanian, the Two Medicine Formation was deposited between the western shoreline of the Late Cretaceous Interior Seaway and the eastward advancing margin of the Cordilleran Overthrust Belt. The Two Medicine Formation is mostly sandstone, deposited by rivers and deltas.
Tyrannosaurs described from the Two Medicine Formation & Judith River Formation; Albertosaurus, Gorgosaurus and Daspletosaurus. Current research from these three Tyrannosaur species has concluded that it's nearly impossible to assign to a specific genus based on teeth alone because they are so similar.

Morphometry of the teeth of western North American tyrannosaurids and its applicability to quantitative classification