I've been reading the Absolute Xenophobe article on TV Tropes and I'm wondering how many alien races in the Star Trek universe fit this description. I can only think of two: the Kh!lict from Windows on a Lost World (a matriarchal crab-like species with two brains) and the Husnock from Fortune of War (a non-humanoid species with seven tentacles). Both of these races are extinct, having been wiped out by angry survivors of their genocidal campaigns. Can anyone think of any others?