First things first, dinosaurs are a diverse group of terrestrial reptiles from the Mesozoic Era. Extinct reptiles like mosasaurus and pterodactyls which lived alongside the dinosaurs, are marine reptiles and flying reptiles, respectively, not dinosaurs themselves.
Now, back to dinosaurs. Saskatchewan is home to dinosaur fossils from two geological time periods of the Late Cretaceous
- The older Campanian (about 72 to 74 million years ago) and
- The younger Maastrichtian (about 66 to 65 million years ago)
The Maastrichtian period contains most of the Saskatchewan's known dinosaurs, including:
- The famous dinosaurs T. rex and Triceratops
- The large hadrosaur ('duck-billed' dinosaur) Edmontosaurus
- The small, bipedal herbivore Thesceolsaurus (the species Thescelosaurus assiniboiensis has only been found in Saskatchewan)
- The less common theropod (bipedal, carnivorous dinosaur) species Sauronitholestes, Dromaeosaurus, and Troodon, plus two or three less well understood small theropods.
- The large 'ostrich-mimic' dinosaur Struthiomimus
- Two rare oviraptors (‘egg-thief’ dinosaurs) called Elmisaurus and Anzu
- Extremely rare horned dinosaur Torosaurus (known only from one specimen) and pachycephalosaurs (‘dome-headed’ dinosaurs; known only from teeth and one partial skull).
The Campanian period in Saskatchewan is not as well represented, as there are only a few locations in the province where these rocks are exposed. Dinosaurs from this period include:
- The ceratopsian ('horned dinosaur') Centrosaurus
- At least one species of crested hadrosaur ('duck-billed' dinosaur)
- At least one large theropod (likely Gorgosaurus or Albertosaurus), and a few species of small theropods
- Vanishingly rare occurrence of ankylosaurs ('armored dinosaurs')
A Gorgosaurus tooth, collected from our Campanian-aged bonebed in Saskatchewan Landing.
Saskatchewan also has Turonian and Cenomanian-aged rocks (about 100 to 90 million years old), but as the province was under the Western Interior Sea at the time, these rocks contain marine fossils rather than dinosaurs. Saskatchewan is actually better known for its endemic marine reptiles and toothed birds than dinosaurs. Species endemic to (endemic meaning 'only found in') Saskatchewan include marine reptiles Terminonatator and Dolichorhynchops herschelensis and the toothed bird Pasquiaornis.