Daspletosaurus torosus

Daspletosaurus torosus was a large tyrannosaurid predator from the Oldman Formation of Alberta. Its deep skull, thick teeth, powerful hind limbs and exceptionally small two-fingered arms show the characteristic body plan that later reached its greatest size in Tyrannosaurus. The type skeleton preserves much of the skull and body, making D. torosus an important reference for the anatomy and evolution of Campanian tyrannosaurines.

Its fossils occur between approximately 77 and 75.6 million years ago. Values shown here are approximate and reflect the current curated seed dataset.

The large, deep skull carried robust, serrated teeth and heavy bony ornament around the eyes and snout. Fused nasal bones strengthened the top of the muzzle. The neck and hind limbs were strongly built, while the forelimbs were extremely reduced but retained two clawed fingers. A long muscular tail balanced the head and torso over the hips.

• Deep, powerfully built tyrannosaurid skull
• Fused and strongly textured nasal bones
• Large serrated teeth with thick roots
• Two-fingered, greatly reduced forelimbs
• Robust hind limbs and muscular balancing tail
• Prominent bony ornament around the eyes

Charles M. Sternberg collected the type specimen, CMN 8506, near Steveville in Alberta in 1921. It was initially referred to Gorgosaurus. Dale Russell recognized its distinctive, more robust anatomy and named Daspletosaurus torosus in his 1970 review of western Canadian tyrannosaurs. The genus name means frightful lizard, while torosus refers to its muscular build.

Discovery credit: Charles M. Sternberg.

Naming authors: Dale A. Russell.

The Oldman Formation records river channels, floodplains and seasonally dry coastal lowlands on western Laramidia. Daspletosaurus shared these environments with horned dinosaurs, hadrosaurs, ankylosaurs and the more lightly built tyrannosaurid Gorgosaurus.

Daspletosaurus was an apex predator equipped to bite and dismember large prey. Tooth marks and healed injuries document feeding and violent encounters, but they do not establish routine pack hunting. Differences between the robust Daspletosaurus and slender Gorgosaurus have inspired niche-partitioning hypotheses that remain difficult to test directly.

• The type skeleton was collected almost fifty years before the species received its name.
• Its name combines Greek words for frightful and lizard.
• The Canadian Museum of Nature displays a largely real Daspletosaurus skeleton in its Fossil Gallery.
• It lived millions of years before Tyrannosaurus rex.

A research repository is not necessarily a public exhibit. Loan and display status can change, so check with the institution before visiting.

1. 01
   The Paleobiology Database

   Open source
2. 02
   Tyrannosaurs from the Late Cretaceous of western Canada

   Dale A. Russell · National Museum of Natural Sciences Publications in Palaeontology 1, 1–34 · 1970

   Open source
3. 03
   Fossil Gallery

   Canadian Museum of Nature

   Open source