Precambrian worm

The Precambrian Worms were a species of giant, fog-dwelling, carnivorous worm from the Precambrian.

Trivia

 * The Precambrian Worms came from further back in time than any other creatures ever known to have come through the Anomalies.
 * Due to their similar physical features, some fans have speculated that the real-life prehistoric worm Ottoia was the young of the Precambrian Worms in the Primeverse. But this is unlikely, as Ottoia was an aquatic lifeform, while the Worms appeared to be land-based creatures.
 * The worms are near identical to the worms from King Kong movie (2005) which Primeval designer Daren Horley also worked on.