An artificial key to 4 endemic species Hemimyzon in Taiwan:

1a Dorsal fin rays 3+7........................................................................ H. formosanus

1b Dorsal fin rays 3+8................................................................................... 2

2a Pelvic fin rays 17......................................................................... H. taitungensis

2b Pelvic fin rays usually14............................................................................... 3

3a Pectoral fin rays 24; lateral-line scales 78-80; the distance of pelvic rear tip to anus about 3 times to that of anus to anal fins.............................................................................................. H. sheni

3b Pectoral fin rays modally 22; lateral-line scales 69-72; the distance of pelvic rear tip to anus about 1.2-1.8 times to that of anus to anal fins......................................................................... H. yushanensis n. sp.