The oriental hornet vespa orientalis (Hymenoptera: Vespinae) cuticular yellow stripe as an organic solar cell: A hypothesis

Many animals such as insects, reptiles, amphibians and marine vertebrates and invertebrates are endowed with bright colors and contrasting patterns intended to warn other animals that they are venomous and such is the case also insofar as the brown yellow coloration of the Oriental hornet. The present work, however, suggests that in the Oriental hornet this is not the only purpose of these bright pigments. The Oriental hornet Vespa orientalis (Hymenoptera, Vespinae) correlates its flight activity with the insolation. The Oriental hornet cuticle bears yellow-colored stripes composed of yellow granules. The yellow granule contains xanthopterin. This array of yellow granules maximizes the ability of the extensively conjugated xanthopterin to absorb a wide range of visible light extending up to UV light. Photovoltaic properties of yellow cuticle evince that the potential difference between darkness and UV illumination is sufficient for ATP production from ADP. This unique photovoltaic behavior of yellow cuticle suggests that it may act as an organic solar cell.