Biological coloration results either from biochromes, which are true pigments that selectively absorb specific wavelengths of visible light, or from schemochromes, consisting of structures that reflect specific wavelengths as a result of the scattering of incident light or interference within the structure (Fox, 1976).
Schemochromes have arisen many times throughout the course of evolution in very distantly related species; but they are particularly prevalent in the tissues of marine animals, in which they are tailored to the limited light environment in which these organisms live (Denton, 1970).
Here we describe unique schemochromes in epidermal cells of the nudibranch F.