"It sat atop the dinosaur pyramid like a sovereign on a throne. It was one of the rarest killers, a monstrous looking predator. It's name: Ceratosaurus. For 20 million years, it was the unchallenged super-predator. Ceratosaurus is the last of it's kind...but more dangerous than ever."

Ceratosaurus ("Horned Lizard")  was a medium sized carnivorous theropod dinosaur that lived at the same time as the larger Allosaurus during Late Jurassic Period, found in the Morrison Formation of North America, and the Lourinhã Formation of Portugal. It's characterized by the blade-like horn on its snout.

It was characterized by large jaws with blade-like teeth, a large, blade-like horn on the snout and a pair of hornlets over the eyes. The forelimbs were powerfully built but very short. The bones of the sacrum were fused (synsacrum) and the pelvic bones were fused together and to this structure (Sereno 1997) (i.e. similar to modern birds). A row of small osteoderms was present down the middle of the back.



Ceratosaurus lived during the Middle and Late Jurassic Period from 176-145 million years ago. It lived alongside dinosaurs like Allosaurus, Camarasaurus, Stegosaurus, and Torvosaurus. It also often preyed upon Dryosaurus and other small herbivores but scavenged off larger kills. However, it also lived some millions of years before the emergence of the successful allosauroids, being of the more primitive four fingered Ceratosauria.

It is probable that the Ceratosaurus ended up being sidelined by the Allosaurus in North America, as evidenced by the fact that Ceratosaurus is the rarest fossil theropod genus present in the magnificent Cleveland Lloyd Dinosaur Quarry. It probably became a prowler of the forest, using its terrifying dentition when ambushing smaller Dinosaurs. Though it is very easy to claim that Allosaurus was more dangerous than a Ceratosaurus overall, being bigger for a start and also being much more numerous as well as advanced, it could be said that Allosaurus represented the Wolf to Ceratosaurus‘s Honey Badger - in that, it may have become a rare but tenacious smaller animal with a nasty aggressiveness that clearly allowed it survive until the end of the Jurassic period.


As a medium-sized predator, Ceratosaurus was small compared to later dinosaurs, such as Tyrannosaurus Rex. Ceratosaurus stood 13 feet (4 meters) tall, measured 20 feet (6 meters) long in length, and weighed 1.5-2 tons (3,000-4,000 lbs.) in weight, making it a mid-sized predator.

What makes Ceratosaurus different and distinctive from most other dinosaurs is the large horn on top of its nose and the two horns over its eyes. About 100 years ago, when it was first discovered, it was one of the most well-known dinosaurs. Another unusual feature is that Ceratosaurus had four fingers on its hands, instead of the more common three among the other large meat-eaters. This is typically an indication that this theropod is relatively primitive, whose ancestral relatives heark back to the earlier times of the Mid Triassic to Mid Jurassic periods when coelophysoideans and ceratosaurians were much more prevalent. Allosaurids and megalosaurian carnosaurs, both kinds tetanurans, were much more advanced, with greater speed and intelligence, as well as the ability in at least allosaurids to form packs.

People tend to look at size being the only important factor, in a sort of 'Top-Trumps' mentality. Sometimes, the small are just as nasty as the large.


Ceratosaurus fossils have been found in North America, Europe, South America, and even Africa, literately a wide-ranging dinosaurs that dominated the Earth.