Pachycephalosaurus
Order: Ornithischia · Suborder: Marginocephalia · Infraorder: Pachycephalosauria · Family: Pachycephalosauridae
Wart-like knobs and five-inch (13-cm) spikes fringed the ten-inch (25-cm) thick dome of Pachycephalosaurus, a rare dinosaur first discovered in Montana. It had a narrow face with leaf-shaped teeth and in all other respects it was like other ornithopods-- two-legged plant eaters with five-fingered hands, three-toedfeet, and a long, heavy tail. Largest and last of the "bone-head"family, it and all its plant-eating relatives and carnivorous cousins became extinct 66 million years ago.
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Reference background: Natural History Museum, London — Dinosaurs; Smithsonian National Museum of Natural History — Dinosaurs; American Museum of Natural History — Dinosaurs & Fossils. Figures are typical published ranges; taxonomy follows the source era and modern consensus is noted where it differs. See our sources & fact-check policy.
Frequently asked questions
What does Pachycephalosaurus mean?
The name Pachycephalosaurus means “Thick-headed Lizard”. It is pronounced pak-ee-SEF-uh-lo-SAWR-us.
When did Pachycephalosaurus live?
Pachycephalosaurus lived during the Late Cretaceous.
Was Pachycephalosaurus a carnivore or a herbivore?
Pachycephalosaurus was a herbivore.
How big was Pachycephalosaurus?
Pachycephalosaurus was about 18 feet (5.5 meters) long, around 10 feet (3.1 meters) tall, weighing up to 4,000 pounds (1,814 kg).
Related dinosaurs
Other dinosaurs from the Pachycephalosauridae family.
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