Appearance
The underside of both sexes is pale greyish brown. The underside hindwing does not have a spot in the basal area of 7. The butterfly has two tails - a 6 mm long one at V1 and a 5 mm long tail at V2. The markings include:⤷ a double bar at end-cell
⤷ a regular discal line on the forewing
⤷ a broken, less regular line on the hindwing
The male butterfly is pale blue to dark brown above, dark shining purple depending on the light. It has a black border with the upper forewing having a large black discal area of modified scales.
The female butterfly is dark brown and its hindwing has a white disconnected discal band above the tornus. The butterfly also has a white-edged tornal black spot in 2.

Naming
The butterfly has a number of subspecies of which one, ''H. e. himavantus'' , is found in mainland India while another ''H. e. andamana'' Moore is found in the Andamans. All subspecies are:⤷ ''H. e. erylus''
⤷ ''H. e. pupienus'' Fruhstorfer, 1912
⤷ ''H. e. teatus'' Fruhstorfer, 1912
⤷ ''H. e. himavantus'' Fruhstorfer, 1912
⤷ ''H. e. andamana'' Moore, 1877
⤷ ''H. e. syphax'' Fruhstorfer, 1912
⤷ ''H. e. gamatius'' Fruhstorfer, 1912 )
⤷ ''H. e. tmolus'' C. & R. Felder, 1862
⤷ ''H. e. orsiphantus'' Fruhstorfer, 1912
⤷ ''H. e. aimnestus'' Fruhstorfer, 1912
⤷ ''H. e. georgius'' Fruhstorfer, 1912
⤷ ''H. e. thyrius'' Fruhstorfer, 1912
⤷ ''H. e. moutoni'' Ribbe
⤷ ''H. e. figulus'' Fruhstorfer, 1912
⤷ ''H. e. erna'' Kalis, 1933
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