Yumme are organisms indigenous to the planet SR388 which use a form of natural chemical rocket propulsion system as their only means to fly. They often emerge from a lair in the ground before moving straight for their intended target to stab them with their sharp thorn, accelerating as they go thanks to their rocket-style movement. As no other feeding method is known, one might come to the conclusion that they do this to take bites, out of their foe as they pass, but this is only speculation. Since SR388 was apparently destroyed in a collision with the orbiting Biologic Space Laboratory Research Station, it may now be extinct and the hypothesis may now never have chance to become theory.
- Metroid II: Return of Samus (First appearance)