User blog comment:Lord Loss/Monster Hunter Theory... Blog/@comment-4098359-20110712124019/@comment-3062343-20110712221014

Another thing that makes Peco Sub inhabiting the Volcano seem odd is that its secondary weakness is fire, which makes living in an area surrounded by all sorts of fire-based monsters seem a very bad idea. Although I believe I had a theory on the Minegarde Theory Topic that the Flooded Forest and the Volcano are close to each other, given that Furogi and Dosufurogi inhabit both, and Rathian and Rathalos inhabit the Flooded Forest and Volcano respectively (not that large distances would bother the Raths too much, but it would make sense for them to remain relatively near each other). Perhaps it's just that Capcom wanted the Peco Sub to inhabit different areas to the regular one, and the Volcano was less far-fetched than the Tundra.