Larval key to the known species of Indian Tenuibaetis Kang & Yang, 1994

1. Posterior margin of terga IV with spines apically rounded..................................................... 2

- Posterior margin of terga IV with spines apically pointed..................................................... 3

2. Dorsal margin of femur with a row of 16–17 long simple setae.................................... T. himani sp. nov.

- Dorsal margin of femur with a row of 23–25 long and blunt setae................................... T. kangi sp. nov.

3. Labrum with U-shaped marking medially; tracheae of gills distinct.................................... T. inornatus

- Labrum without U-shaped marking medially; tracheae of gills absent............................................ 4

4. Dorsal margin of tibia with spatulate setae and tarsi short spine-like setae; paraproct with about 20 marginal spines; length of caudal filament vs. cerci ratio 0.6×.............................................................. T. frequentus

- Dorsal margin of tibia and tarsi with only thin setae; paraproct with about 14 marginal spines; length of caudal filament vs. cerci ratio 0.75×.................................................................................... T. arduus