Pachycephalosaurus wyomingensis

Pronunciation: PASK-ee-SEFF-uh-low-SORE-us, wyy-OME-ing-EN-sis
Meaning of name: Thick-headed lizard from Wyoming

Length: 9 feet (3 meters)
Weight: Estimated 250 pounds (115 kg)
Diet: Plants
Range: North America (Alberta, Montana, South Dakota, Wyoming)
Age: Late Cretaceous, 68-65 million years ago

What is it?: Pachycephalosaurus belongs to a group of dinosaurs called pachycephalosaurs (domed dinosaurs), which are related to ceratopsians (horned dinosaurs).