Nocturnal butterflies in Panama, Hedylidae (Lepidoptera: Rhopalocera)

Abstract Butterflies (Rhopalocera) are the most conspicuous and familiar members of the order Lepidoptera. Their diurnal activity together with their habit of visiting flowers brings them into close proximity with people, and their often colourful wings cause us to notice them. However, it is not only the butterflies that are diurnal and colourful among Lepidoptera. Diurnal behaviour has arisen several times in the order, usually accompanied by colourful wings. The moth families Castniidae, Zygaenidae, Geometridae, Uraniidae, Sphingidae, Arctiidae (in several subfamilies), and Agaristidae all include some diurnal and colourful members, and many people who see them just assume that they are butterflies. Several of these moth families are comprised of exclusively diurnal species, but most of the largest ones are predominantly nocturnal groups. When one considers that, among the close to 120 families of Lepidoptera, diurnal examples can be found only in these few families of moths plus the six families of true butterflies, it becomes apparent that the day-flying habit is actually rather rare. The butterflies themselves are in a distinct minority; they represent only about 10 per cent of lepidopteran species.