Phylogeography and variation in sexual characters in Argia moesta damselflies (Odonata: Coenagrionidae): a test of the lock and key hypothesis

Damselflies are a textbook example of "lock and key" genital variation between species. Intense scramble competition for mates is presumed to explain elaborate variation in sexual characters across species. However, some species show variation in secondary sexual morphology within species. Argia moesta is a species of coenagrionid damselfly that is found from Canada to Argentina and has been reported to vary in sexual character morphology across its range. We present the first study of intraspecific sexual character variation in an evolutionary context for this widespread and common species.