Dustox is based on the Japanese Moon Moth, a species that is closely-related to and looks almost identical to the Luna Moth.There definitely needs to be a Pokémon based on the Luna Moth!
They're an absolutely gorgeous, green moth. Fairly large. They're mostly nocturnal, as far as I'm aware, and they're a pretty good size.
Personally, I'd make it a Bug/Dark type, part of a two or three evolution line, and would give it decent enough stats to make it useful in the main game's story. It could be named Lunoth.
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However, Dustox is definitely lacking in the beauty department compared to the real thing. Shame it didn't get a Mega in ORAS that brought out more of these attractive features.
On the subject of moths, I'd love to see a Rosy Maple Moth Pokémon! They pretty much look like real-life Pokémon.
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(I've already tried making one myself, as you can see in my avi.)