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)
Aaglon sharks were creatures native to Olleril. (NA: Tragedy Day)
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)
The planet Philjax III was home to a species reminiscent of sharks. (DWBIT: #9)