The N. nubilus species-group

Characterized by dark coloured (grey brown with silvery gloss) species, length of antennae in males about 1.25 the forewing length. In male genitalia, valva elongated flap-like, almost membranous throughout the length with only the margins sclerotized; costa slightly concave, ventral margin roughly straight; sacculus process broad rectangular with a small, setose apical flap; another setosed flap at the centre of inner wall of valva and in closely proximity of the apical flap of the sacculus process.