Board Thread:Metal Gear Solid V/@comment-26691987-20151016025936/@comment-6747658-20151016122235

The Morpho Butterfly was a bit of a different name for Peacewalker, it was mentioned by Strangelove when she talkes to Snake. It's also the butterfly shown several times within Peacewalker.

Morpho, the heli, most likely got it's name also due to similar reasons.