The blue morpho is famous for brilliant blue wings created mainly by microscopic scale structure rather than blue pigment.
Blue morphos are butterflies in the genus Morpho, a group native to Central and South America. Their wing surfaces contain layered scales with extremely fine ridges. These structures reflect particular wavelengths of light, producing structural coloration that appears intensely blue from suitable angles.
The blue color is most conspicuous when a morpho flies through rainforest shade, where flashes of blue can appear and disappear rapidly. The undersides of the wings are generally brown and patterned, helping the butterfly blend into leaves when it rests with its wings closed.
“Blue morpho” is a common name used for several closely related Morpho species, so it is not one single universally accepted species name. Morpho menelaus is one well-known blue morpho species. The butterflies are not the world’s largest, but their broad wings can make them look especially dramatic in flight.