Abstract
The phylogeographic structure of insect species in North America is poorly understood. The moth family Sesiidae (Lepidoptera) contains many economically important pests of agriculture and forestry, as well as beneficial species used in biological control. Despite their significance, this study constitutes the first broad-ranging population genetic study on North American sesiids. It probes the population structure of eight species of sesiid moths based on sequence variation in cytochrome c oxidase I (N = 191). Haplotype diversity levels were high in seven of the eight species, while nucleotide diversity varied considerably. Patterns ranged from limited structure and a starburst pattern in the raspberry crown borer Pennisetia marginata to highly geographically structured populations in the peachtree borer Synanthedon exitiosa and the maple callus borer Synanthedon acerni. These varied patterns suggest differing evolutionary histories and dispersal abilities. By elucidating population genetic structure and barriers to dispersal we can begin to devise conservation and management plans.