Fabricius put it in the (masculine) genus Pterophorus so gave the species the masculine ending too, as the the system has the genus a noun and the species an adjective, so in Latin the adjective must agree in gender with the noun it describes. Subsequently the species was moved to the genus Megalorhipida, a feminine noun, so some taxonomists ,(like those in AFD) changed the suffix to match, and some (like those in iNat) didn't.