Look at a full moon in the autumn, when the sky is black. That's what the wings of the great eggfly male look like, and why it's also called the blue moon butterfly. Females of this sexually dimorphic species lack the bright white spots ringed in blue that males display.
Great eggfly butterflies live in the South Pacific islands, Australia, New Zealand, Madagascar, and southeast Asia.
Adults nectar on tropical flowers. The larvae feed on leaves of a variety of perennials, including arrowleaf sida and common purslane.