Butterfly

From Tardis Wiki, the free Doctor Who reference

Butterflies were Earth lepidopterids K9 once encountered on an unnamed planet in another dimension, partially inhabited by ex-Tellac miners.

They lived alongside other Earth animals from widely varying periods of evolutionary history. Unlike most species of butterfly on modern Earth, however, these had a wingspan of about ten feet, as many extinct species did on Earth in the prehistoric past. (AK9: K9 and the Missing Planet)

Romana joked to Rohm-Dutt that she had been catching butterflies in the swamps of Delta III. (DW: The Power of Kroll)

Butterfly