Jared Voris is no stranger to death. By early 2018, the University of Calgary master’s student had spent more than a year poring over bones in museum collections, studying how tyrannosaurs matured from hatchlings into hulking terrors. During one visit to the collections of Alberta’s Royal Tyrrell Museum of Palaeontology, he noticed a cabinet with fossils he couldn’t quite place.

Now, after two years of careful research, Voris and his colleagues have identified the first new Canadian tyrannosaurid to be found in 50 years. Stretching 26 feet in length, the dinosaur is named Thanatotheristes, Greek for “reaper of death.”

Aged roughly 79.5 million years, Thanatotheristes degrootorum sits near the base of the tyrannosaurs’ ascent to ecological domination. The unearthed skull fragments—including upper