Vengas

Vengas are a type of insect found in the Forest Temple in The Legend of Zelda: Spirit Tracks. They normally skitter around relatively aimlessly, but when attacked, they bloat up and burst into a small cloud of noxious fog. They are first found as a group of four in a miniboss encounter, the reward for which is the whirlwind. After this, they can be found elsewhere in the temple, including places Link has already been to. Due to their similar coloration and connection to the toxic gas, they are likely related to Stagnox, the temple's boss.