Flutterwing

Flutterwings were a species of insect native to the planet Gallifrey. Romana studied their life cycle while at the Time Lord Academy. They likely went extinct when Gallifrey was destroyed at the end of the Last Great Time War. (DW: The Pirate Planet, NA: Set Piece) The Doctor kept a flutterwing in his TARDIS's butterfly room. (PDA: Vampire Science)


 * It was not specified on-screen what kind of animal the flutterwing was, only in the novel.