MORPHOLOGY
External characteristics
Male
Forewing length (mm): 41-44. Wingspan (mm): 65-74.
Forewings: Upperside creamish with black to dark brown pattern as follows: all veins broadly darkened, cross bars in cell, margin broadly dark with complete series of submarginal spots, in apical region dark pattern more or less strongly fused into a dark area in which the internervular creamish areas are reduced to spots; underside similar, but dark pattern brown rather than black Hindwings very slightly crenulate, no tail; upperside and underside as forewing, complete series of curved, submarginal spots.
Female
Forewing length (mm): 45-49. Wingspan (mm):74-80.
Similar to male.
Subspecies and variation
Varies strongly in the extension of the dark pattern; three subspecies are recognized.
Similar species
A bit similar to G. megarus, but the broad dark border of the hindwing is better defined. For the similarity with the genus Parantica (Nymphalidae:Danainae), see under G. megarus.
source: Jan Moonen, peronal communication 2020