MORPHOLOGY
External characteristics
Male
Forewing length (mm): 32-42. Wingspan (mm): 53-68.
Forewings: Upperside creamish with brown to blackish brown pattern of narrowly or broadly darkened veins and crossbands in cell, dark border with complete series of submarginal spots; underside similar, but paler Hindwings very slightly crenulate, no tail; upperside and underside as in forewing.
Female
Forewing length (mm): 36. Wingspan (mm):60.
As male.
Subspecies and variation
Dark color can extend so far from the veins as to give the impression of a dark butterfly with creamish spots. Part of the variation is geographic, seven subspecies are recognized, of which five occur in the Malaysian area.
Similar species
Similar to species of Parantica (Nymphalidae: Danainae), a poisonous genus. Papilionidae can always be distinguished by the possession of only one anal vein in the hindwing instead of two.
source: Jan Moonen, peronal communication 2020