Euchrysops cnejus males have pale purple upper wings with orange spots on space 1b and 2 hind wings, while females are pale blue shining in base areas, brown outlines on both wings and hind wings have submarginal spots that are prominent and bordered by dark lines. The underside is gray-brown in color with a series of pale brown marginal, submarginal and post-discal spots. On the hind wings there are three black spots in the basal area, one black spot on the costal and two crowned orange tornal spots in chambers 1b and 2, having a white tipped tail at the tip of vein 1b.
Larva: Euchrysops cnejus larvae are yellowish green in color with a dark, narrow dorsal band bordered by white bands on both sides. Widened in cylindrical shape, the surface of the body is covered with short and smooth white setae.
Pupa: Euchrysops cnejus pupae are yellowish green in color with small black spots on the surface of the body arranged symmetrically around the dorsal line. It is typically lycaenid in shape and has short, smooth white setae on the anterior end and body.