Key to Charissa (Pterygnophos) species: male genitalia structures

(Abbreviations in brackets refer to Fig. 1a)

1 Sclerotized dilation present close to base of costa (sd)....................................................... 2

- Without sclerotized dilation close to base of costa........................................................... 3

2 Sclerotized dilation (sd) with serrate keel, juxta (ju) almost symmetrical..................... C. (P.) beljaevi spec. nov.

- Sclerotized dilation swollen with minute spines, juxta usually distinctly asymmetrical................. C. (P.) creperaria

3 Valva processes (vp) about half of costa length, length of ventral valva margin (vm) 2.2–2.9 mm, without costal thorns............................................................................................. C. (P.) agnitaria

- Valva processes about 1/5 of costa length, length of ventral valva margin 2.0– 2.3 mm, with costal thorns..................................................................................................... C. (P.) ochrofasciata