..., bile pigments and carotenoids colour butterfly wings (Barbier, 1981 ; Stavenga et al., 2010). The pterin pigments of pierids are concentrated in strongly scattering granules (Yagi, 1954 ; Ghiradella et al., 1972 ; Stavenga et al., 2004), but the other pigment classes are diffused throughout...

... (Fig. 4). The reflectance spectrum of the pale-yellow wings of P. xuthus is low in the ultraviolet wavelength range (except for a minor reflectance band peaking at 320 nm) and high above 500 nm. Such a spectrum can be readily understood to result from virtually wavelength-independent scattering...

... showed that the orange barbs contain small pigment granules. The cyan and blue barbs contain spongy nanostructures with slightly different dimensions, causing different reflectance spectra. Imaging scatterometry showed that the pigmented barbs create a diffuse orange scattering and the spongy barb...