Inconspicuous structural coloration in the elytra of beetles Chlorophila obscuripennis (Coleoptera)

The elytra of male beetles Chlorophila obscuripennis (Coleoptera) display an inconspicuous iridescent bluish green color. By structural characterizations we find that the outermost elytral surface comprises a sculpted multilayer, which is the origin of structural coloration. In elytra both structural green and cyan colors are observed which arise from the modulations imposed on the multilayer, leading to a bluish green color by color mixing. The adoption of the sculpted multilayer can render structural coloration inconspicuous, which could be advantageous for camouflage. In addition, it can cause light emergence at nonspecular angles.