Dracorex was a species of pachycephalosaur (bone-headed) dinosaur that lived during the Late Cretaceous. One was mistaken for a dragon by medieval people and likely inspired the mythical beast.


Dracorex was a dinosaur genus of the Pacycephalosauridae family, which possessed powerful hind legs and a horned skull. In behaviour, although not truly vicious, Dracorex was still fearfully aggressive towards larger animals such as humans. Normally, at the signs of nearby activity from them, a Dracorex would prefer to flee, but would sometimes instead attack if too close.

Incursions and encounters

Episode 3.7

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The Dracorex in the Medieval age. (Episode 3.7)

A female Dracorex came through an Anomaly to a forest sometime in the Medieval ages. The people of the town sheltered in the church while Sir William de Mornay pursued the creature, believing it to be a dragon. The Dracorex was badly wounded when Sir William stabbed a stake into its side, and the creature fled from him through another Anomaly into a London junkyard in the present.

There, the Dracorex was almost killed when a worker in the junkyard on the present day side of the Anomaly tried to defend himself against it with a car-crushing crane. When the ARC team arrived and stopped the worker, the Dracorex initially charged, and the team tried to scare it back through the Anomaly. However, the Dracorex refused to return to the Medieval times through the Anomaly, and escaped and fled the junkyard as Sir William came through.

The Dracorex later travelled through a field to a strawberry farm, scaring off the workers. Abby Maitland and Hilary Becker found the Dracorex eating the fruit, and the creature charged at the two. However, it collapsed under the stress of its wound from Sir William's stake before Becker could shoot it.

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The Dracorex while being treated by Abby. (Episode 3.7)

Abby and Becker subsequently transported the unconscious Dracorex back to the junkyard, where they began operating on it to remove the stake. When Sir William found the Dracorex, he initially tried to slay the unconscious creature until the team convinced him against it. After Sir William returned to his time, Abby decided to keep the Dracorex until the ARC encountered an Anomaly back to its home to return it through.

Episode 4.1

After the ARC was revived, the Dracorex was kept in the new ARC building's Menagerie. It was also nicknamed Princess. While maintenance was being carried out, Jess Parker accidentally freed Princess from the Menagerie by opening the airlock too early. The Dracorex rampaged through the ARC and had a brief confrontation with Matt Anderson, before making its way to the ARC's main hub.

In the hub, Princess cornered Jess, but was then distracted by James Lester's untimely arrival. Matt then lured Princess into Lester's office with a bucket of water, and locked the Dracorex inside. After finishing the water, Princess began to trash Lester's office until Becker went in and tranquilised it. Princess was then presumably returned to the Menagerie.

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The Dracorex rampages through the ARC. (Episode 4.1)

Episode 4.4

Due to the inconvieniences of keeping and caring for the creatures in the Menagerie, Philip Burton planned to have all of them (presumably including Princess) put down. However, Philip aborted this plan when Lester blackmailed him.

Episode 5.4

When the First Man-made Anomaly released a gamma ray into the ARC, Abby stated that the creatures in the Menagerie (presumably including Princess) would have been protected from the gamma ray by the Menagerie's lead-lined walls. Therefore, assuming the Future Beetle infestation never chewed into the Menagerie, the creatures, including Princess, presumably survived.

Real life

Dracorex (name meaning "dragon king") lived in North America during the Late Cretaceous period, approximately 66 million years ago. The only paleontological evidence of Dracorex to be discovered was a complete skull and four cervical vertebrae, found in South Dakota. However, Dracorex's official identity as its own dinosaur genus has been questioned by some, who suspect Dracorex to actually be a juvenile Pachycephalosaurus.


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The Dracorex running in a field. (Episode 3.7)

  • The Dracorex was the first non-theropod dinosaur to appear in the Primeval show.
  • Dracorex was either a herbivore or omnivore. Due to its sharp pointed teeth, the Dracorex in Primeval was likely the latter, although Connor called it a herbivore. However, if it were to eat meat, it would presumably only eat small insects or invertebrates for protein.


  • The Dracorex in Episode 3.7 was referred to as being male, while in Episode 4.1 it was referred to as female.
  • Due to the lack of fossil evidence, the Primeval Dracorex had some speculative physical traits/differences:
    • The Dracorex was portrayed as having a mouth full of sharp, needle-like teeth, but most pachycephalosaurs had a toothless beaks with most of the teeth closer to the back of the mouth.
    • It had a pair of sails on its back to give it a more dragon-like appearance.
    • The horns were longer and thinner than they were in life, and looked more like the famous devil horns of a different species called Stygimoloch spinifer.