Great Purple Emperor

Sasakia charonda, the Great Purple Emperor, belongs to Nymphalidae. In Japan it is known as Ōmurasaki and is the national butterfly. [3][5]

Males have iridescent purple-blue upper wings, whereas females are predominantly brown. Pale spots and warmer hindwing markings remain useful identification characters in both sexes. [3]

The species is recorded in Japan, Korea, China and Taiwan. Central Japanese surveys associate it with riparian and secondary woodland. [7][8]

Tama Forest Science Garden in Japan describes one annual adult flight period in July and August. Larvae overwinter in leaf litter beneath Celtis sinensis. [4]

At Tama Forest Science Garden in Japan, larvae feed on Celtis sinensis and adults visit tree sap. [4]

Japanese observations describe vigorous male flight around tree crowns. Korean accounts include adults obtaining moisture at ground level and males visiting hilltops in the afternoon. [3][7]

A 2010 study of male Sasakia charonda charonda found that layered cuticle and air in wing-scale ridges produce interference colours, including purple-blue and pearly white. Yellow, red and brown regions differed in their pigment contributions. [6]

The genus honours Chujirō Sasaki, associated with entomological work in Tokyo, including sericulture and insect pests. Sasakia charonda is Japan’s national butterfly and is known there as Ōmurasaki. [5]

The male’s dorsal purple-blue iridescence changes with illumination and viewing angle. The ventral surface has a different pattern, while the female’s dorsal wings are predominantly brown. [3][6]

Scott Schubr’s illustration emphasizes the male’s purple-blue field, pale spots and warm hindwing accents. Bold linework preserves the wing structure while flat colour conveys the characteristic pattern.

Protect framed specimens from direct daylight, moisture, pests and handling damage. Inspect the enclosure and avoid touching scales when examining colour. [1]