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Certain Drosophila species that cannot mate in darkness have also been shown to be unable to mate in the light if their wings have been removed, perhaps due to the fact that wings provide visual signs and signals for courtship. To determine the influence of winglessness on mating in light-dependent Drosophila algonquin and its relatives, we determined mating frequencies in combinations of winged and wingless individuals of the six widespread American Drosophila affinis subgroup species D. affinis, D. algonquin, D. athabasca, D. azteca, D. narragansett, and D. tolteca. In no case did winglessness of either females or males prevent mating altogether, though there were varying reductions of mating frequency with winglessness. Wingless males of D. algonquin mated with winged females as well as winged males, while wingless females of this species mated with winged males significantly less often than did winged females. It does not appear that the male courtship wing display of D. algonquin provides an essential visual stimulus for mating. On the other hand, it seems likely that the female's appearance, including presence of wings, is important for the male's orientation just before copulation. Our data also suggest that winglessness influences mating by impairing auditory signals and, perhaps, by reducing mobility and coordination.