New Tyrannosaur Species Discovered, Nicknamed "Reaper of Death"

Move over, Tyrannosaurus Rex. You may be the nightmare-inducing King of the Tyrant Lizards, but you're no longer the scariest tyrannosaur. Researchers with the University of Calgary and the Royal Tyrrell Museum in Canada have identified a new, fearsome species in the tyrannosaur family and the new discover comes with a truly horrifying name that means "reaper of death" -- the Thanatotheristes degrootorum. The discovery is the first new tyrannosaur species to be identified in Canada in half a century according to Edmonton Journal and is the oldest known tyrannosaur discovered in the country.

The discovery was made by University of Calgary Ph.D. candidate Jared Voris who noticed that skull fragments stored in a drawer at the Royal Tyrrell Museum had features that other tyrannosaur specimens didn't have.

"We'd find one feature, and then we'd find another, and then it would just kind of cascade into finally understanding that this was something completely different than what we'd seen before," Voris explained.

As for what makes this dinosaur unique? The "Reaper of Death" has various skull differences from other tyrannosaurs, including prominent vertical ridges that run the length of the upper jaw.

The new species got its name, Thanatotheristes degrootorum, as a combination of the Greek word for "reaper of death" along with the name of the Alberta couple, the DeGroots, who discovered the fragments in 2010. According to Voris' Ph.D. supervisor Darla Zelenitsky, the "Reaper of Death" predates the well-known and much-feared T. rex by around 12 million years and offers new insight into what is a period of history that is not well understood -- especially with "Reaper of Death" being the first meat eater to have been found in that area from that time. The other two were both plant-eaters, making this new discovery very interesting.

"This is the first apex predatory dinosaur species known from this formation," Zelenitsky said.

The "Reaper of Death", it should be noted, is not believed to be a direct ancestor of T. rex. The new discovery appears to have more in common with another type of tyrannosaur that's been found in Alberta previously, one called Daspletosaurus. Still, the discovery is an exciting one.


"To me this is a big discovery and it's even more exciting because it was made by one of my students."

What do you think about this new "Reaper of Death" dinosaur? Let us know in the comments below!