Several species of unidentified creatures have occurred in Primeval.
Several flocks of an unknown type of Pterosaur were seen flying above the Cretaceous beach and desert. (Episode 1.3, 2.2) One or two Pterosaurs were seen flying in the distance from a forest in the Cretaceous. Though they were most likely Pteranodon. (Episode 3.10/4.1)
- Several unidentified Pterosaurs appeared in a Episode 1.5 promo image despite not appearing in the actual episode.
A Badger like Mammal was a creature from the Early Cretaceous. The Anomaly Research Centre team encountered one Badger-like mammal in the Cretaceous coastal woodland eating a deceased Iguanodon calf. When startled, it snarled at the team and ran away into the undergrowth. (The Lost Island)
- It was possibly Repenomamus, a three foot long Early Cretaceous mammal that is known to have fed on small dinosaurs. It also may be either an undiscovered species of Mesozoic mammal or perhaps even a Didelphodon (which would be unlikely as it lived in the Late Cretaceous).
Some shrew-like creatures came through an Anomaly from the Cretaceous and were captured by the Tunguska research team in Tunguska Siberia and kept in a small building used by the team used for captured specimens. Cutter observes a pair of small shrew-like creatures scuttling around in a tank, while explaining to Abby how the mammals inherit the earth after the K-T event. Later, these creatures were possibly seen feeding on deceased Anatotitan. (Extinction Event)
The crested bird had a crest of feathers on top of its head and a large claw on each foot, so it most likely evolved from Theropod raptors.In an area of Russia, where live specimens of Cretaceous life forms had been collected by the Tunguskan Research Team, Nick Cutter stopped to look at a tiny crested bird in a wire cage that was captured. One of the men described how rare the bird was, as tiny-boned creatures rarely remain intact in fossilisation. (Extinction Event)
A Sparrow-like Pterosaur was found frozen in Tunguska. The Tunguska research team found it and kept it preserved. (Extinction Event)
Four theropods of a unknown species were seen playing in the distance from the Cretaceous forest. (Episode 3.10). A year later, Abby Maitland had a sketch of another theropod, possibly the same species. (Episode 4.1)
- The CGI models used in Episode 3.10 appears to Giganotosaurus.
Small Future Birds
- As the bird's time period was presumably only a matter of centuries in the future, the birds may have similar biology as modern day birds.
Creature Sightings creatures
Several unidentified creatures were seen on several websites as Connor Temple searched for creature sightings. (Episode 4.2) The websites were:
- There was a herd of unidentified sauropods in the Cretaceous coastal woodland. (The Lost Island)
- Two unidentified theropods were captured by Tom Samuels. (Fire And Water).
- On some occasions, creatures were heard but not seen;
- Several creatures were heard on the Future Rainforest (Episode 3.5).
- Some creatures roared in the Cretaceous forest, though they may have been Raptors or the unidentified Theropods. (Episode 3.10)
- Captain Becker faced an unknown carnivore during Convergence. It squealed after Becker shot it with an EMD. (Episode 5.5)