Ceratosaurus
Order: Saurischia · Suborder: Theropoda · Infraorder: Ceratosauria · Family: Ceratosauridae
Ceratosaurus was found in western North America. It has horns above and forward of its eyes, resembling those of Allosaurus, but it Ceratosaurus derives its name from its extremely unusual, rather large nose horn. Because Ceratosauruswas a very large predator, it is not likely that the horn was a weapon. Possibly it was a secondary sex characteristic, identifying males or females; perhaps it was used in ritual mating battles between males. It has also been suggested that the horn was used by hatchlings to break out of their eggs.
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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 Ceratosaurus mean?
The name Ceratosaurus means “Horned Lizard”. It is pronounced sih-RAT-uh-SAWR-us.
When did Ceratosaurus live?
Ceratosaurus lived during the Late Jurassic.
Was Ceratosaurus a carnivore or a herbivore?
Ceratosaurus was a carnivore.
How big was Ceratosaurus?
Ceratosaurus was about 20 feet (6.1 meters) long, around 13 feet (4.0 meters) tall, weighing up to 3,000 lbs (1,360 kg).
Related dinosaurs
Other dinosaurs from the Ceratosauridae family.
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