Delayed color maturation of a sexual ornament in males of a damselfly: crypsis, female mimicry or both?

Dynamic signals are a widespread phenomenon in several taxa, usually associated with intraspecific communication. On the other hand, dynamic iridescent signals are only detectable at specific angles of illumination; hence, the animal can hide the signal to avoid detection when necessary. This structural coloration is mostly dependent on illumination, contrast against the background and the vision of the receiver. Complex behavioural displays may be coupled with structural coloration to create dynamic visual signals that enhance these functions. Here, we addressed whether iridescence of males of a damselfly that inhabits dark rainforests, Chalcopteryx scintillans, can be considered a dynamic visual signal. We analyzed if coloration is perceived by conspecifics, while reducing detectability to eavesdroppers against three background types. Our results suggest that the visual background affects the detectability of male hindwings by different receivers, mostly predators and prey. We discuss...