Key to pupae of Rheotanytarsus from South America [emended from Wiedenbrug & Ospina–Torres (2005)]
1. Tergites IV–VII with paired fields of dark-colored reticulation; shagreen present on tergites V–VI, absent on tergite VII ................................................................................................ Rheotanytarsus sp. 1 Wiedenbrug & Ospina–Torres
- Tergites IV–VII not as above ...................................................................................................................................... 2
2. Three taeniate lateral setae on segment VIII. ............................... Rheotanytarsus sp. 2 Wiedenbrug & Ospina-Torres
- Lateral setae on segment VIII not as above.................................................................................................................. 3
3. Tergites II–VI with paired anterior patches of spinules, bifid ventral setae, segment VIII with darkened margins and two caudolateral spurs ................................................................................................. Rheotanytarsus lamellatus Reiss
- Tergites II–V with paired anterior point patches, segment VIII never as above. ......................................................... 4
4. Segment VIII with 5 taeniate lateral setae ................................................................... Rheotanytarsus globosus Reiss
- Segment VIII with 4 taeniate lateral setae.................................................................................................................... 5
5. Tergite II with paired anterior transverse point patches and fine shagreen in the middle of tergite (Wiedenbrug & Ospina-Torres 2005, fig. 5 C) ...................................................... Rheotanytarsus sp. 3 Wiedenbrug & Ospina-Torres
- Tergite II with only paired anterior transverse point patches, without fine shagreen in the middle of tergite (Wieden- brug & Ospina-Torres 2005, fig. 5 I) ........................................... Rheotanytarsus sp. 4 Wiedenbrug & Ospina-Torres