Munge Dweevil
Mandarachnia pungetis
The Munge Dweevil is an enemy in the Pikmin 2 game. This Dweevil is commonly seen retrieving bug bodies and treasures. The purple creature, (when agitated by attacks), will release a cloud of gas that will poison your Pikmin. This suitably makes White Pikmin the best choice in battle, as they are immune to poisoning. Alternatively, as Purple Pikmin can stun any small Dweevil, they will easily defeat one.
Olimar's Notes
The Munge Dweevil is one member of an insect family known for mimicking objects by carrying them on their backs. These insects often carry the carcasses of other life-forms on their backs, but apparently this is not for the purpose of transporting them as food, but instead is another example of their mimic behavior. The Munge Dweevil produces two different chemical compounds within its body, which form poisonous gas when mixed and expelled. This gas is only used for self-defense.
Louie's Notes
Exposure to even extreme heat doesn't seem to rid this creature of deposits of potent gas. It's probably best for everyone if you avoid eating this hazardous fare.
How to Kill
Pikmin
Attack it with whites. If you don't have White Pikmin, it's probably better to kill it with your captains. Purples also work as they have a hundred percent chance of stunning any small Dweevil.
Captains
Run up to it and attack it. Don't worry though, Olimar and Louie/the President are already immune to poison.