Excalibosaurus is a species of icthyosaur from the Early Jurassic with a flattened upper jaw like a sawfish. It probably hunted fish and squid.
An Excalibosaurus attacks and injures a fisherman in the Thames. When the ARC Team get there, Connor, Cutter, Danny, and Abby get on a boat and look for the anomaly and an Excalibosaurus leaps out of the water. Danny shoots the creature and it falls back into the water. Just then the anomaly closes. Connor decides to put the creature in the menagerie. They return to shore and decide they will have to try to draw it to them. Matt goes and buys a large fish and hooks it to a string which he throws into the water. They spot the Excalibosaurus swimming toward it and prepare to shoot at it with their EMD's. The creature finally gets close enough and they shoot it and work together to drag it up. They transport it to the ARC's menagerie.
- It is shown to attack anything it sees as a threat.
- It is quite aggressive in Primeval Continued.
- It is slightly larger than the real creature.
- The resemblance of Excalibosaurus' rostrom to a sawfish's rostrom was exaggerated for the show.
- It was probably more aggressive than the real creature.