About Papilio dehaanii
This species, Papilio dehaanii, is size variable by season of emergence. Individuals that emerge in spring reach 4 to 8 centimeters in wingspan, while summer-emerged individuals can reach 12 centimeters. The forewings are black with dark veining and green scales; their undersides are brown, turning white toward the distal end with dark veining. The hindwings are tailed, have ridged edges, and contain reddish eyespots. The body is black with green scales. Males have black hair on their forewings, which females lack. The species is also discussed as P. bianor in Seitz, being very variable both geographically and seasonally. For males, pilose stripes are broad; the posterior three are usually united. If these stripes are separated, the stripe of the lower median remains broader than the interspace that separates it from the stripe of the submedian fold. The upper surface of the male forewing is dusted with green or green-blue scaling, which is commonly condensed into a band before the narrowly dark distal margin. The upper surface of the male hindwing is blue or blue-green anteriorly and dusted with green posteriorly, and usually has a more thickly scaled large green or blue patch (or a similar band), a red anal spot, plus 0 to 4 red submarginal spots and at least some distinct green submarginal spots anteriorly. The black basal area on the underside of the forewing always extends beyond the base of the upper median, and sometimes the entire forewing is black. The underside of the hindwing has a complete row of red submarginal spots. Females have less dense metallic scaling, and the red spots on the upperside of the hindwing are usually more numerous and larger than those of males. This butterfly occurs from North Japan to Tonkin and West China, and appears to be fairly common across all of its local range, sometimes occurring in large numbers. Like its closely related species, males congregate on moist sand and visit flowers. The larva is green with 2 to 8 light oblique bands, and feeds on Aurantiaceae. This description was authored by Karl Jordan in Seitz.
