Brontotholus

Say it like this: “BRON-toe-thole-luss”

Brontotholus harmoni

Brontotholus ate plants and walked on two legs. It lived in the Late Cretaceous. Bones have been found in the United States.

Quiz me on Brontotholus

When: Late Cretaceous (Campanian) · roughly 83.6 to 72.2 million years ago
Named in: 2025 · Woodruff, D. C.; Horner, J. R.; Goodwin, M. B.; Evans, D. C.
Hip height: Not established
Length: 3.8 m · 12 ft
Weight: Not established
Found in: the United States · Two Medicine
Food and walking: Herbivore · Two legs
Kind: dome-headed dinosaur · Pachycephalosaur
Family branch: Pachycephalosaurinae

The story in short

The genus Brontotholus dates to 2025, the year D. C. Woodruff and colleagues described it.

It lived in the Late Cretaceous (Campanian), roughly 83.6 to 72.2 million years ago. Finds come from the United States, including the Two Medicine Formation. It was a herbivore and walked on two legs.

Published estimates put Brontotholus at a length near 3.8 m.

On the family tree it sits in Pachycephalosaurinae, among the dome-headed dinosaurs.

Close relatives

Acrotholus

Acrotholus audeti

Late Cretaceous (Santonian) · roughly 85.7 to 83.6 million years ago

Alaskacephale

Alaskacephale gangloffi

Late Cretaceous (Maastrichtian) · roughly 72.2 to 66 million years ago

Foraminacephale

Foraminacephale brevis

Late Cretaceous (Campanian) · roughly 83.6 to 72.2 million years ago