The N. cinerealis species-group

Characterized by light coloured (with light to dark silvery grey tinge) species, length of antennae in males about twice the length of the forewing. In male genitalia, valva elongated flap-like with its basal half almost membranous, the distal half sclerotized; costa slightly concave, almost straight; ventral margin of valva outwardly angled in the middle; distal sacculus process hooked dorsad, reaching almost the centre of the valva; an elongated ridge with a patch of long simple setae at the centre of the inner wall of the valva, in close association with the tip of the distal saccus hook.