The origin, evolutionary malleability, and sometimes loss of insect wings, gossamer structures whose existence has reshaped the natural world, is one of the most interesting and enigmatic dramas of insect biology. Lampyridae have long been known for the reduced wings that occur in females of some genera, but in all previously known examples it is a fait accompli, with little or no intraspecific variation. Such variation occurs in and among populations of the little daytime firefly Pyropyga nigricans, and also, among these populations there appears to be variation in sexual involvement in the phenomenon, with brachypterous males also occurring at some localities. This firefly provides an opportunity for students, both in summer classes and as solitary individuals, to study the evolutionary biology of wings, from adaptive significance to sexual selection and population ecology and genetics, to speciation, and in a variety of habitats from strands on northern glacier lakes to southwestern montane stream sides and beyond, to west-coast marshes.