Nanotyrannus

dwarf tyrant

• nanos · Greek · dwarf
• tyrannos · Greek · tyrant

The name combines the Greek words for "dwarf" and "tyrant". It was chosen because the original skull, found in 1942 and named in 1988, was small and was thought to belong to a separate, small tyrannosaur. The name reflects that interpretation, which was long debated as the skull might instead be a juvenile Tyrannosaurus.

Named by

Bakker, Williams and Currie

Year named

1988

Period

Late Cretaceous

Stage

Maastrichtian

Found in

Hell Creek Formation, Montana, USA

The genus was long regarded by many researchers as a juvenile Tyrannosaurus, based on the holotype skull (CMNH 7541, originally named Gorgosaurus lancensis by Gilmore in 1946). A 2025 study of the "Dueling Dinosaurs" specimen argued that Nanotyrannus is a distinct, valid genus of small, fully grown tyrannosaur. The issue is still discussed, so check recent literature.