The blue is not pigment. It is the structure of the wing scales bending light, which is why it flashes and vanishes as the butterfly beats along a trail, and why the underside is dull brown with eyespots when it lands and folds up.
Where you’ll see it
Shady tracks, stream edges and forest with a canopy. On the dry coast around Coco they are an occasional treat. In the green hills inland they are regular, and the rainy season brings many more.
What to know
Adults feed on rotting fruit rather than flowers, so a fallen mango is a better lure than a garden. They fly in a slow, bouncing way along regular routes, often the same stretch of path each morning. Stand still and one may pass within arm’s reach. Every photograph you have seen of the open blue wings was taken while it was feeding.
