Key to the species of the genus Diduga in Cambodia based on the external morphology

1. Forewing dark brown ground color, with deep yellow margins along the costa and distally............................ 2

- Forewing dark brown ground color, without deep yellow margins along the costa and distally......................... 7

2. Forewing with yellow margins along basal to termen, which lower edge of margins not rugged.............. D. amoenusa

- Forewing with yellow margins along costa and termen, which lower edge of margins rugged.......................... 3

3. Brown part of forewing irregularly “Z” or “S”˗shaped; hindwing gray, slightly tinged with pale brown.................. 4

- Brown part of forewing irregularly triangular; hindwing brown................................................. 5

4. Brown part of forewing more slender; hind border of deep yellow costal margin one time strongly angled in medially; covered with dark brown dots in apical and terminal margin................................................... D. barlowi

- Brown part of forewing broader; hind border of deep yellow costal margin two times weakly angled in medially and basally; several dark brown dots in apical margin.................................................... D. bispinosa n. sp.

5. Hindwing with a dark brown patch of androconia................................................... D. albicosta

- Hind wing without a dark brown patch of androconia......................................................... 6

6. Hind border of deep yellow margins with deep angle in apical area and tornus; hindwing dark brown.... D. dubatolovi n. sp.

- Hind border of deep yellow margins with shallow angle in apical area and tornus; hindwing gray brownish.................................................................................................. D. kohkongensis n. sp.

7. Forewing with a discoidal pale dot; hindwing brown, with a dark patch of androconia...................... D. alternota

- Forewing with a discoidal pale brown dot; hindwing brown, without a dark patch of androconia.............. D.annulata