Key to species of Potamonautes in Lake Kivu (Cumberlidge & Meyer 2011) and its drainage basin (present work)

1. Postfrontal crest complete, either distinct or faint............................................................ 2

- Postfrontal crest either incomplete or absent................................................................ 4

2. Anterolateral margin toothed; s3/s4 incomplete, not meeting top of sac; exorbital tooth large, pointed....... P. lirrangensis

- Anterolateral margin smooth; s3/s4 complete, meeting top of sac; exorbital tooth either small or reduced to granule....... 3

3. Mandibular palp with small hard flap at junction between segments; lateral fold of G1 terminal article higher than medial fold.............................................................................................. P. minor

- Mandibular palp simple, lacking hard flap at junction between segments; medial fold of G1 terminal article higher than lateral fold...................................................................................... P. perparvus

4. Medial and lateral margins of dorsal membrane of G1 uneven; s2/s3 faint or incomplete............................ 5

- Medial and lateral margins of dorsal membrane of G1 even; s2/s3 deep, completely crossing sternum................. 6

5. Distal meral tooth of P1 merus reduced to granule; terminal article of G1 slim, straight, tapering evenly to tip. P. bourgaultae

- Distal meral tooth of P1 merus distinct, pointed; terminal article of G1 slim at base, significantly widened in middle, tapering sharply to narrow tip...................................................................... P. gonocristatus

6. s3/s4 complete, meeting top of sac; G1 terminal article straight....................................... P. idjwiensis

- s3/s4 incomplete, not meeting top of sac; G1 terminal article curved............................................ 7

7. First carpal tooth low, blunt; subterminal segment of G1 with setose margins.......................... P. muta nd ensis

- First carpal tooth distinct, pointed; subterminal article of G1 lacking setae.............................. P. semilunaris