Wasp Moth

The moth has a wingspan of 34 mm. The frons and collar are yellow with the metathorax having a yellow streak. The first abdominal segment has a yellow band which is sometimes obsolescent. The fore wing has large hyaline patches, one filling the cell, another filling nearly the whole interno-median inter-space, one at junction of veins 2 and 3, two subapical, and two submarginal. In the form S. i. sargania, there is a long streak between veins 5 and 6. In others it is reduced to a spot or may be lacking entirely. The hind wing has a postbasal hyaline patch extending hardly (or not at all) beyond the cell. The tips of the antennae and proximal joints of the tarsi are white. The spots of the fore wing vary considerably in size.