MORPHOLOGY

External characteristics

Male
Forewing length (mm): 55-56. Wingspan (mm): 94-96.
Forewings: Upperside black, veins in cell inconspicuously paler, very indistinct paler double stripes between the veins; underside similar, but venation in cell and stripes more conspicuous, particularly from tornus to mid wing, where they may be almost whitish. Hindwings strongly crenulate with strong spatulate tail at end of vein 4; upperside black with large, irregular, pale yellowish patch from front margin to vein 5, consisting of four spots (in spaces 4-7), the upper one (in space 7) about half to 2/3 as wide as spot in space 6; underside pale patch continued with increasingly narrower spots to inner margin, small pale yellow spot at margin at tornus, two dark red stripes on both sides of vein 8.

Female
Forewing length (mm): 57. Wingspan (mm):100.
Similar to male, but upperside about as underside male, except on the upperside no red stripes on both sides of vein 8.

Subspecies and variation

Not recorded. The species has a restricted range in the northern part of Sumatra and geographic variation appears improbable.

Similar species

By the extended pale yellow band and red stripes on the underside easily distinguished from congeners.

_{source: Jan Moonen, peronal communication 2020}