A male (left) and swallow-tailed female Great Mormon. These large butterflies, with a wingspan of between 12 and 15 centimeters, are commonly found in Thailand and are widely distributed through Southeast Asia. There are several subspecies and forms.

Males are tailless and dull in colour (i.e. mostly black and deep blue, sometimes with a red spot on the forewing - fig.), and females being multi-coloured, with black, pale gray, reddish orange and dark yellow, and with some female forms having a swallowtail.