The Achilles morpho, or blue-banded morpho, is a neotropical butterfly, found in rainforest habitats at altitudes between sea level and 1000m. It is a widespread species with 8 named subspecies, found from Colombia, Venezuela and Guyana, south along the astern Andes to Peru and Bolivia. This specimen comes from Argentina.
The dazzling blue wings of morpho butterflies are enormous relative to their body size, resulting in a very distinctive slow, bouncy flight pattern. The effect is that the brilliant blue upperside appears to flash like a beacon as it alternates in flight with the dark undersurface. This makes it difficult for a bird to follow the flight. If attacked when on the wing, the slow lazy flight pattern instantly changes into a wild swooping evasive manoeuvre, following which the butterfly dives into the forest where it instantly settles. A pursuing bird is still of course searching for a brilliant blue insect, but the morpho snaps its wings shut, displaying the dark brown underside and foiling the bird's search program. If the bird does manage to spot the settled butterfly it invariably aims its attack at the most prominent feature - in this case the ocelli, missing the body entirely and allowing the butterfly to escape.
Males of achilles patrol back and forth along rivers and streams, searching for females. They are most active in the mornings, and spend most of the afternoon visiting sap runs, feeding at rotting fruit or sitting motionless on foliage in the darkness of the forest. Females are seen far less frequently.
Both sexes close their wings immediately upon landing, but periodically flick them open to give the briefest glimpse of the dazzling blue upperside. This behaviour is most pronounced in mud-puddling males, which repeatedly flicker their wings as they hop about on the ground seeking dissolved minerals.
The refractive properties of the scales on the wings has been studied as a model in the development of biomimetic fabrics, dye-free paints, and anticounterfeit technology used in currency.
A brief bit of internet wisdom about refraction:
The microscopic scales covering the morphos’ wings reflect incident light repeatedly at successive layers, leading to interference effects that depend on both wavelength and angle of incidence/observance. Thus, the colours appear to vary with viewing angle, but they are actually surprisingly uniform, perhaps due to the tetrahedral (diamond-like) structural arrangement of the scales or diffraction from overlying cell layers. The wide-angle blue reflection property can be explained by exploring the nanostructures in the scales of the morpho butterfly wings. These optically active structures integrate three design principles leading to the wide-angle reflection: alternative lamellae layers, Christmas tree-like shape, and zigzag pattern of the ridges. The reflection spectrum is found to be broad (about 90 nm) for alternating layers and can be controlled by varying the design pattern. The Christmas tree-like pattern helps to reduce the directionality of the reflectance by creating an impedance matching for blue wavelengths. In addition, the zigzag pattern of ridges destroys the unwanted interference for other wavelengths in wide angle.
The butterfly has been prepared in the UK to museum standards and is displayed in a deep handmade shadowbox frame, mounted on white conservation-grade foam. The back of the frame is covered in really special Italian decorative paper, with a brass hook for hanging it on the wall (but it also stands perfectly on a mantlepiece or a table). It is completely sealed inside the frame and will last for generations.