The four butterflies featuered are the Monarch Butterfly (Danaus plexippus), the Postman Butterfly (Heliconius melpomene), the Mazarene Blue Butterfly (Polyommatus semiargus) and the Old World Swallowtail (Papilio machaon). When the flashlight that is included with the set is shined on the coins, the butterfly wings light up in luminescent splendor.