Dry-season form - Upperside black, with pure white markings.
Forewing discoidal streak clavate (club shaped), apically truncate, subapically either notched or sometimes indistinctly divided; triangular spot beyond broad, well defined, acute at apex, but not elongate; discal series of spots separate, not connate (united), each about twice as long as broad; postdiscal transverse series of small spots incomplete, but some are always present.
Hindwing: subbasal band of even or nearly oven width; discal and subterminal pale lines obscure; postdiscal series of spots well separated, quadrate or subquadrate, very seldom narrow.
Underside from pale golden ochraceous to dark ochraceous almost chocolate; white markings as on the upperside, but broader and defined in black.
Forewing: interspaces 1a and 1 from base to near the apex shaded with black, some narrow transverse white markings on either side of the transverse postdiscal series of small spots.
Hindwing a streak of white on costal margin at base, a more slender white streak below it; the discal and subterminal pale lines of the upperside replaced by narrow white lines with still narrower margins of black.
Antennae, head, thorax and abdomen black; the palpi, thorax and abdomen beneath dusky white.

Wet-season form - Differs only in the narrowness of the white markings and in the slightly darker ground colour and broader black margins to the spots and bands on the underside.

This species has been observed to make sounds whose function has not been established.
Dry-season form - Upperside black, with pure white markings. Forewing discoidal streak clavate (club shaped), apically truncate, subapically either notched or sometimes indistinctly divided; triangular spot beyond broad, well defined, acute at apex, but not elongate; discal series of spots separate, not connate (united), each about twice as long as broad; postdiscal transverse series of small spots incomplete, but some are always present. Hindwing: subbasal band of even or nearly oven width; discal and subterminal pale lines obscure; postdiscal series of spots well separated, quadrate or subquadrate, very seldom narrow. Underside from pale golden ochraceous to dark ochraceous almost chocolate; white markings as on the upperside, but broader and defined in black. Forewing: interspaces 1a and 1 from base to near the apex shaded with black, some narrow transverse white markings on either side of the transverse postdiscal series of small spots. Hindwing a streak of white on costal margin at base, a more slender white streak below it; the discal and subterminal pale lines of the upperside replaced by narrow white lines with still narrower margins of black. Antennae, head, thorax and abdomen black; the palpi, thorax and abdomen beneath dusky white.
Wet-season form - Differs only in the narrowness of the white markings and in the slightly darker ground colour and broader black margins to the spots and bands on the underside.
This species has been observed to make sounds whose function has not been established.
Neptis hylas