The Brown Gorgon, Meandrusa sciron, is a species of swallowtail found in parts of South Asia

South Asia

South Asia, also known as Southern Asia, is the southern region of the Asian continent, which comprises the sub-Himalayan countries and, for some authorities , also includes the adjoining countries to the west and the east...

 and Southeast Asia

Southeast Asia

Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...

. It belongs to the Hooked Swallowtails genus , Meandrusa, of the Papilionidae family. The butterfly is found in India from Sikkim to Assam and North Burma and is not considered to be threatened. Though not uncommon, it is protected under Indian Law under the name 'gyas'.

Description

For terms used in the description see Glossary of Lepidopteran terms

Glossary of Lepidopteran terms

This glossary describes the terms used in the formal descriptions of insect species, jargon used mostly by professionals or entomologist....

Male

Upperside opaque brown, the basal area and the terminal third of both fore and hind wings of a darker shade than the broad medial area, due to the dark markings of the underside that show through by transparency; fore and hind wings with a subterminal series of largish yellow lunules that curve upwards posteriorly on the hind wing and end in a diffuse transverse bluish-white mark across interspace 1. Underside, fore wing: basal third and a large spot on the discocellulars, that is widened anteriorly, rich dark cinnamon-brown; medial third lilacine, pale towards the dorsum, widened anteriorly and extended into the apex of the cell, and on the costa from the discocellulars to near the apex of the wing; interspaces 2, 3 and 4 with paler lilacine lunules; terminal third of the wing dull brown, with a postdiscal and a subterminal transverse series of somewhat obscure olivaceous-yellow lunules Hind wing: basal third rich dark cinnamon-brown in continuation of that colour on tho fore wing; remainder of tho wing lilacine, with a large posterior discal patch of cinnamon-brown, margined inwardly by a diffuse broad irregular white band, and outwardly by a series of white lunules; a subterminal somewhat obscure row of olivaceous-yellow markings; the tail and terminal margin dark cinnamon-brown. Antennae dark brown, head, thorax and abdomen brown with an olivaceous tinge ; beneath: similar, the abdomen more brightly olivaceous yellow.

Female

Upperside: ground-colour similar to that in the male; marking differ as follows:—a very broad discal transverse lilacine white band across both fore and hind wings that extends from vein 5 and from within the apex of cell of fore wing to tho dorsal margin of the hind wing. Fore wing: a yellowish-white costal spot in upper third of cell, a larger spot beyond that turns to yellow at base of interspace 6, an anterior postdiscal transverse series of yellow more or less lunular spots, and a subterminal similar series of spots. Hind wing: the lilacine white colour of the discal band spreads to the base of the wing, but is thickly irrorated with brownish scales, as is also the outer margin posteriorly of the same band; the rest of the wing dark brown, with the margins of the tornus and of the tail broadly bright cinnamon-brown; lastly, superposed on the brown area is a sub-terminal series of large, yellow, well-defined more or less lunular spots. Underside similar to that of the male, the ground-colour and markings on the outer two-thirds of both fore and hind wings paler. Antennae, head, thorax and abdomen as in the male.

Other references

• Collins, N.M., Morris, M.G. (1985) Threatened Swallowtail Butterflies of the World. IUCN. ISBN 2-88032-603-6
• Wynter-Blyth, M.A., (1957) Butterflies of the Indian Region, Bombay Natural History Society,Mumbai, India.