Queen bat

From Tardis Wiki, the free Doctor Who reference

Queen bats were large, hairy bat-like creatures that lived in the caves of Androzani Minor.

Biology

They had a three year life cycle, some of which was spent in a chrysalis. These chrysalises had a large supply of unrefined Spectrox, which was refined and used by the humans of Androzani Major. (TV: The Caves of Androzani)

History

The bats were killed or driven out by the mining androids, which caused them to move into the airless caves deep underground to die. (TV: The Caves of Androzani)