01775nas a2200157   4500008004100000245013100041210006900172260000800241300001200249490000800261520125300269100001501522700001801537700001801555856004401573       2004                        eng d00aRemarkable iridescence in the hindwings of the damselfly Neurobasis chinensis chinensis (Linnaeus) (Zygoptera: Calopterygidae)0 aRemarkable iridescence in the hindwings of the damselfly Neuroba  cMar  a595-6010 v2713 aThe bright green dorsal iridescence of the hindwings of Neurobasis chinensis chinensis males, very rare in Odonata, is known to play a significant role in their courtship behaviour. The mechanism responsible for such high contrast and spectrally pure colour has been investigated and found to be optical interference, producing structural colour from distinct laminations in the wing membrane cuticle. The ventral sides of these iridescent wings are dark brown in colour. In a single continuous membrane of wing cuticle, this is an effect that requires a specialized structure. It is accomplished through the presence of high optical absorption (kappa = 0.13) within two thick layers near the ventral surface of the wing, which leads to superior dorsal colour characteristics. By simultaneously fitting five sets of optical reflectivity and transmissivity spectra to theory, we were able to extract very accurate values of the complex refractive index for all three layer types present in the wing. The real parts of these are n = 1.47, 1.68 and 1.74. Although there is often similarly significant dorsal and ventral colour contrast in other structurally coloured natural systems, very few system designs comprise only a single continuous membrane.1 aVukusic, P1 aWootton, R, J1 aSambles, J, R  uhttps://odonatas.myspecies.info/node/59