Quitoxin

The Quitoxins were species capable of quickly regrowing their limbs. Quitoxin space ships used Sevinium Drives.

The Doctor encountered members of this species twice. The second time he met one was in his eighth body while travelling with Lucie Miller. This particular Quitoxin was altering the DNA of several soldiers in Little Morton, turning them into Quitoxins. It planned to convert all of humanity, but the Doctor defeated it by telepathically stunning it. He then dematerialised the Quitoxin along with its ship with his TARDIS and took it to an uninhabited planet. (AUDIO: The Young Lions)