Key to species of Hyadina from the Oriental Region
1. Wing with five faint white spots at least....................................................................................................................... 2
- Wing with three faint white spots at most .................................................................................................................... 3
2. Wing with five faint white spots; femora and tibiae yellow ............................................. H. quinquepunctata sp. nov.
- Wing with nine faint white spots; legs reddish brown .................................................................... H. pulchella Miyagi
3. Wing with two faint white spots at most ...................................................................................................................... 4
- Wing with three faint white spots ................................................................................................................................. 5
4. Wing with two faint white spots on anterior and posterior sides of posterior crossvein .................. H. sauteri Cresson
- Wing without faint white spots ..................................................................................................... H. hivaoae (Malloch)
5. Faint white spots on anterior and posterior sides of posterior crossvein and below posterior crossvein; male cercus thickened basally and slender apically .................................................................................... H. longicaudata sp. nov.
- Faint white spots on anterior and posterior sides of posterior crossvein and above anterior crossvein; male cercus short and thickened ................................................................................................................... H. jinpingensis sp. nov.