Frog

From Tardis Wiki, the free Doctor Who reference

Frogs were amphibious creatures native to Earth.

Earth frogs

When the Axons offered axonite to the people of Earth, they used it to make a frog grow in size, demonstrating how it could be used to solve world hunger. (DW: The Claws of Axos)

Other frogs

On Monarch's ship, frogs were used for their poison by the Monarch. The poison had the power to shrink living people. (DW: Four to Doomsday)

Josiah W. Dogbolter was half-frog, half-man. (DWM: The Moderator)

On an unnamed planet, the First Doctor, John and Gillian met a race of hat-wearing talking frog people and helped them catch a shark that was trying to eat them. The frog people helped them search for the the TARDIS when it disappeared. (TVC: Shark Bait)

References

On the planet Chloris, the Fourth Doctor suggested that a giant frog was responsible for laying a giant egg there. (DW: The Creature from the Pit)

Frog