User blog comment:Mckrongs/Monster Hunter 4 for the Nintendo 3DS/@comment-21378804-20131003110715/@comment-4212769-20131003134025

Baleful Gigginox is a mutation as well (also said in the game)

Khezu is the albino form of the Red Khezu (again information by Pike that knows that by the Ecology Books and stuff, I think but for sure Capcom official information).

Same for the Rath Subspecies.