The Ceratosaurus was a medium-sized theropod dinosaur that lived in North America during the Upper Jurassic period, around 161–146 million years ago. It was a carnivore that was closely related to the Allosaurus and Stegosaurus.

Known for its short, rounded snout with large nostrils and a hollow crest on top, the Ceratosaurus had a long slender body with a long tail that made it resemble a crocodile.

Key Facts

Ceratosaurus pronunciationkeh-rat-oh-sore-us
What does Ceratosaurus mean?Horned Lizard
Dinosaur typeTheropod
On the menuCarnivore
Length20 ft (6 m)
Height5.2 ft (1.6m)
Weight1443 lb (650kg)
Life expectancyUnknown
Legs used to get aroundBipedal
Estimated top speedUnknown
When they livedUpper Jurassic, 161-146 million years ago
Where they have been found?North America

When & Where

The first Ceratosaurus remains were accidentally discovered and later excavated in 1883–1884 by a farmer, Marshall Parker Felch, in Green Park Colorado. These nearly-complete remains were found in the Jurassic Morrison Formation and were the first of its species to be discovered.  

Othniel Charles Marsh later gave the Ceratosaurus its official name and description in 1890.

Size & Weight

The Ceratosaurus was a medium-sized dinosaur, measuring roughly 20 ft in length, and weighing a massive 1443 lb. It had a long slender body with a long tail and limbs but rather small arms. 

The Ceratosaurus was adorned with a large, ridge-like horn on its snout, two horns over the eyes, and deep jaws that housed long, blade-like teeth.

Mobility & Diet

The Ceratosaurus was bipedal, meaning it walked on two legs. Its tail could be used as a counterweight to help keep its body balanced and is believed to have been very agile. With its short front legs, it would have been able to move very quickly and easily change directions.

As a carnivore, the Ceratosaurus is believed to have preyed upon smaller sauropods and the abundant theropods in the late Jurassic period.

Interesting Points

  • Ceratosaurus means “horn lizard”, derived from the Greek words keras (κέρας), meaning “horn,” and sauros (σαυρος), meaning “lizard” or “reptile.”
  • The tail of the Ceratosaurus made up to half of its entire length.
  • More Ceratosaurus remains have since been discovered in different countries on different continents, like Uruguay, Tanzania, Switzerland, and Portugal.

Featured Image Credit: Debivort at English Wikipedia, CC BY-SA 3.0, via Wikimedia Commons