Shark

Sharks were a type of predatory fish.

In Atlantis, the Doctor, Ben, Polly and Jamie were nearly fed to sharks as a sacrifice to Amdo. (DW: The Underwater Menace)

In the 1970s, the Australian branch of UNIT discovered a fragment of Brokk's spaceship in the belly of a shark. (MA: The Eye of the Giant)

On an unnamed planet, the Doctor, John and Gillian helped a race of intelligent frogs catch a shark that was trying to eat them. (TVC: Shark Bait)

The Pescatons apparently evolved from sharks or a shark-like species. (Doctor Who and the Pescatons)

The Selachians dressed as sharks to intimidate their enemies in battle. (PDA: The Murder Game, The Final Sanction)