The male flagellum of 32 North American tiger beetle (Cicindela Linnaeus; Coleoptera: Carabidae: Cicindelinae) species was examined with a scanning electron microscope for new, stable characters that might be useful in studies of taxonomy and functional morphology. Two sets of characters were observed, shape and size of the flagellum, and the form and distribution of tempers (micro teeth-like structures on the surface of the flagellum). These characteristics were surprisingly uniform for most species. It is inferred that the inner walls of the female spermatheca duct are gripped by the male flagellum, achieved either by flexing the inserted temper-free long flagellum, or direct insertion by the temper-covered short flagellum. It is proposed that an inverse relationship pattern exists between the elongate temper-free flagellum, and the temper-covered shorter flagellum.