Temporal range: Middle Jurassic
Proceratosaurus bradleyi by primevalraptor-d5p0k8v
An artist's illustration of Proceratosaurus bradleyi
Scientific classification
Kingdom: Animalia
Phylum: Chordata
clade: Dinosauria
Order: Saurischia
Suborder: Theropoda
Superfamily: Tyrannosauroidea
Family: Proceratosauridae
Genus: Proceratosaurus
Friedrich von Huene, 1926
Species: P. bradleyi
Binomial name
Proceratosaurus bradleyi
Arthur Smith Woodward, 1910 [originally Megalosaurus]
  • Megalosaurus bradleyi (Woodward, 1910)

Proceratosaurus ("before Ceratosaurus" or “before horned lizard) is a genus of small-sized (9.8 feet long) theropod dinosaur from the Middle Jurassic. It is a tyrannosauroid that fed on insects, lizards, mammals, and frogs. It lived in England. It has a small, pointed crest on its snout that looks similar to that of Ceratosaurus. The type and only species of the genus is named P. bradleyi.

Despite its size, Proceratosaurus was a fast and deadly carnivore. Its closet relatives are Chinese Guanlong and Russian Kileskus. Proceratosaurus would become the precursor to larger tyrannosaurs like Daspletosaurus, Alioramus, Yutyrannus, Gorgosaurus, and the fabled Tyrannosaurus.

History of discovery[]

The specimen was discovered during excavations some time prior to 1910 for a reservoir near Minchinhampton, a town located in the Cotswolds in Gloucestershire, England. The upper part of the skull was missing due to fissure that had eroded the rock, and was partially filled with calcite.


Arthur Smith Woodward, who initially studied Proceratosaurus, originally thought it to be an ancestor of the Late Jurassic Ceratosaurus, due to the similarity of their nasal crests. Later study during the 1930s by Friedrich von Huene supported this interpretation, and Huene thought both dinosaurs represented members of the group Coelurosauria.

It was not until the late 1980s, after Ceratosaurus had been shown to be a much more primitive theropod and not a coelurosaur, that the classification of Proceratosaurus was again re-examined. Gregory S. Paul suggested that it was a close relative of Ornitholestes, again mainly due to the crest on the nose (though the idea that Ornitholestes bore a nasal crest was later disproved). Paul considered both Proceratosaurus and Ornitholestes to be neither ceratosaurs nor coelurosaurs, but instead primitive allosauroids. Furthermore, Paul considered the much larger dinosaur Piveteausaurus to be the same genus as Proceratosaurus, making Piveteausaurus a junior synonym.[7] However, no overlapping bones between the two had yet been exposed from the rock around their fossils, and future study showed that they were indeed distinct.

Paleobiology and Ecology[]

Proceratosaurus possessed a nasal crest, which may have served as a form of sexual display or intraspecific competition but also possibly served to reduce bending stresses on the skull when biting.

It lived alongside other theropods, including Megalosaurus and Eustreptospondylus, sauropods, such as Cetiosaurus, stegosaurs, like Lexovisaurus, and ornithopods, like Callovosaurus and Camptosaurus.

In popular culture[]

  • In Jurassic Park (film), Proceratosaurus can be seen to the far right of the embryo storage chamber next to Gallimimus.
  • Proceratosaurus first appeared in the video game Jurassic World: Evolution, as a smaller sized carnivore, in the carnivore pack update.
  • Proceratosaurus also appears in the Amazon Prime series Dino Dana in the first musical episode, The Sound of Dinosaurs.
  • Proceratosaurus appears in Jurassic World: Alive as a feathered, epic rarity creature.