Key to species of the genus Onryza (mainly traced from Evans, 1949)

1. Hindwing upperside without sharply marked small spots......................................................2

- Hindwing upperside with two sharply marked spots in spaces Cu2 and M3.........................................3

2. Forewing upperside spots in spaces Cu2 and M3 quadrate, completely overlapped........................... O. siamica

- Forewing upperside spots in spaces Cu2 and M3 elongated, partly overlapped............................... O. meiktila

3. Hindwing underside veins yellow.........................................................................4

- Hindwing underside veins black.............................................................. O. pesudomaga

4. Hindwing underside black spots conspicuous..................................................... O. maga maga

- Hindwing underside black spots faint or absent................................................ O. maga takeuchii