Nacaduba berenice, the rounded six-line blue,[1][2][3] is a lycaenid butterfly found in Indomalayan realm.

[1][2] Male upperside: dull purplish blue, in certain lights with a shining plumbeous (lead-coloured) frosting.

[4][5] Female upperside: fuscous brown, the veins prominent; an elongate oval medial patch extended from base outwards on forewing for about two-thirds of its length, dull brownish white brilliantly iridescent with metallic blue in certain lights.

Underside: pale ochraceous brown; markings much as in the male, but of the transverse white lines that cross the disc of the forewing the outer one is shorter, not extended below vein 3.

Underside: very dark purplish brown; markings in form and arrangement much as in the female of the typical form, but the transverse bands formed by the white lines much broader; on the hindwing the black subterminal spots in interspaces 1 and 2 much larger, conspicuously crowned inwardly and surrounded with ochraceous orange and with an outer bordering of metallic green scales; the anteciliary black line edged inwardly over the tornal area with white.