Key to known males of Brazilian Pseudochironomini

1. Fore tibial comb with a long spur....................................................... Pseudochironomini ….2

- Fore tibia without comb....................................................................... Chironomini

2. Wing with dark marks; anal point present and well developed; median volsella long.................. Aedokritus Roback

- Wing without marks; median volsella if present, not long...................................................... 3

3. Pars ventralis present.......................................................... Pseudochironomus Malloch …4

- Pars ventralis absent or, if present, represented by 2 triangular lobes basally fused to gonocoxite..................... 10

4. Posterior margin of tergite IX with median notch............................................................ 5

- Posterior margin of tergite IX without median notch.......................................................... 7

5. Adult male length> 4.0 mm, wing length ± 3.0 mm......................... P. ruah Shimabukuro & Trivinho-Strixino

- Adult male length <4.0mm, wing length <3.0 mm...........................................................6

6. Tergite IX with protruding end projecting from the tergite; median volsella thin with one apical seta and another seta right above it........................................................ P. mocidade Shimabukuro & Trivinho-Strixino

- Tergite IX without protruding end; median volsella thin, bearing 2 long and strong apical setae........................................................................................ P. jordensis Shimabukuro & Trivinho-Strixino

7. Pars ventralis completely divided, leaf-shaped; median volsella with 1 apical seta and other one subapical................................................................................ P. surianae Shimabukuro & Trivinho-Strixino

- Pars ventralis divided or partially divided at the apex, not leaf shaped; median volsella with 2–3 apical setae............. 8

8. Pars ventralis completely divided; median volsella rounded with 2 setae............................ P. ariquemis sp. n.

- Pars ventralis fused or partially divided at the apex; median volsella short semi triangulate............................9

9. Superior volsella with a sclerotized internal projection; median volsella with 1-2 simple setae........... P. boraceia sp. n.

- Superior volsella without a sclerotized at internal projection; median volsella with 2–3 simple setae...... P. capivara sp. n.

10. Superior volsella with short ventral digitus............................................... .. Manoa obscura Fittkau

- Superior volsella without digitus........................................................... Riethia Kieffer ....11

11. Tergite IX with unusual caudal projection resembling an inverted U; inferior volsella very large and distally truncated............................................................................................... R. fazzari sp. n.

- Tergite IX without caudal projection; inferior volsella not as above............................................. 12

12. Superior volsella short and hooklike; inferior volsella triangular with 2–3 distal marginal large and curved scales.................................................................................................. R. galilei sp. n.

- Superior volsella long; inferior volsella not triangular, with or without marginal scales.............................. 13

13. Inferior volsella without marginal scales and with about 20 flattened and apically pectinated scales setae.............................................................................................. R. truncatocaudata (Edwards)

- Inferior volsella with marginal scales and less than 20 flattened and apically pectinated scales........................ 14

14. Inferior volsella with marginal long and large scales.............................................. R. cauame sp. n.

- Inferior volsella with large marginal scales................................................................ 15

15. Inferior volsella with 7 marginal broad scales and 6 apically pectinate dorsal setae..................... R. pantera sp. n.

- Inferior volsella with 3 marginal distal flattened scales and 15 apically pectinate................................................................................................. R. manauara Neubern, Trivinho-Strixino and Silva