Genus Elcysma Butler, 1881

Type species: Elcysma translucida Butler, 1881 by monotypy (currently a junior synonym of Agalope westwoodii Vollenhoven, 1863)

Diagnosis. Superficially unmistakable among Chalcosiinae by having translucent wings and “tailed” hindwing. Elcysma is characterized by the combination of the following characters: 1) On hindwing, outer margin forms a tail-like projection just below the apex, veins M 2 and M 3 stalked. 2) In male genitalia, the distal sclerotized section of costa and sacculus fuse at the distal end of the valva and form a short spiniform distal process. 3) Juxta lobes long (ca. 2 × length of the basal section of juxta) and broad (ca. 0.5 × width of the basal section of juxta), the gap between the juxta lobes is V-like, the depth is nearly a half of the totally length of the juxta. 4) The subscaphium is sclerotized and U-shaped. 5) In female genitalia lamella postvaginalis present, band-like.

Distribution. From Japan through Korean peninsula, Russia Far East, most parts of mainland China except the northwestern part to Northeastern India and Northern Indochina.

Species composition

E. westwoodii (Vollenhoven, 1863) (Figs 49, 50, 63, 91, 92, 107, 119)

E. dohertyi Elwes, 1890

E. delavayi Oberthür, 1891

E. ziroensis Chada, Gogoi & Young, 2017