3.1 Nemophora albiantennella species group

Diagnosis. This species group can be distinguished by the following characters: the forewing color is uniform without fasciae, usually yellowish green, bronze, or copper with bright metallic luster; the completely fused base of valva; the suspensorium is very short, not reaching the base of valva; and the apex of aedeagus consists of dorsal and ventral lobes.

Remarks. Three species belong to the albiantennella species group. Among them, N. insulariella is distributed in Sakhalin, Russia (Kozlov 1997a), and N. albiantennella is a widespread species from northern China to the Russian Far East. In addition, N. pseudalbiantennella sp. nov. is a new and endemic species in Shaanxi Province, China.

Key to species of the albiantennella group based on external morphology

1 Tibiae of leg yellowish to brown; abdomen uniformly brown to dark brown.......................... N. albiantennella

- Tibiae of leg black; abdomen most yellowish to brown with black apex.................. N. pseudalbiantennella sp. nov.

Key to species of the albiantennella group based on male genitalia

1 Valva triangular, with straight lateral margins; suspensorium very small, distinctly far away from posterior margin of vinculum............................................................................... N. albiantennella

- Valva nearly trapezoid, lateral margins concave basally; suspensorium relatively large, close to posterior margin of vinculum........................................................................... N. pseudalbiantennella sp. nov.