After obtaining the national pokedex, Dustox can be found at these areas THEY ARE RARE Eterna Forest Route 205 (North) Route 224 Route 229 Route 230
Dustox.
Eterna forest
DUSTOX
You can find a dustox in eterna forest and there is also a trainer with dustox there too.
I think that Team Galactic's members usually have Dustox.
You are able to get Dustox by evolving Cascoon. Wurmple-Silcoon-Beautifly Wurmple-Cascoon-Dustox
you can find it in the survival area
I think it's Dustox
Dustox can be found in Eterna Forest. it can also be found by battling these two bug catchers
eterna forest 10%
Cascoon evolves into Dustox at level 10
Wurmple can go one of two ways, it can evolve into a Silcoon or a Cascoon. Silcoon evolve into Beautifly. On the other hand, Cascoon evolves into Dustox.