MORPHOLOGY
External characteristics
Male
Forewing length (mm): 19-25. Wingspan (mm): 30-41.
Forewings: Upperside and underside forewing blackish brown, in apical half a large transparent area, narrow near tornus, strongly widening to space 6, then narrowing again towards apex, dark margin narrow, much narrower than dark cross band from tornus to front margin; latter band towards wing base followed by whitish green cross band from mid hind margin to front margin, which again is followed by the blackish brown wing base; underside similar, greenish band rather whitish, ochreous scaling at wing base. Hindwings Upperside hindwing blackish brown with a conspicuous green or whitish green band from front margin to tornus, narrowing and ending well before tornus; underside with ochreous scaling in basal part and in patches along inner margin to tornus.
Female
Forewing length (mm): 23-24. Wingspan (mm):36-38.
Similar to male.
Subspecies and variation
Little variation, but ten subspecies have been recognized, seven of which occur in the Malesian area.
Similar species
The very long pointed tails of the hindwings make the genus unmistakable. The other species of the genus, Lamproptera curius, is similar, slightly smaller, the transparent area on the forewing is decidedly narrower, the black margin clearly broader, and the black band from tornus to front margin strongly widens towards the front margin, instead of having almost parallel sides.
source: Jan Moonen, peronal communication 2020