Rheotanytarsus pellucidus (Walker, 1848)

Key to known adult males of the Rheotanytarsus pellucidus View in CoL species group

( Based on the key in Kyerematen et al. 2000)

1. Median volsella relatively short, not reaching apex of inferior volsella........................................... 2

- Median volsella very long, extending beyond apex of inferior volsella........................................... 3

2. Inferior volsella curved and sharply pointed at apex; superior volsella widest at apex; median volsella with wide, nearly circular apical plate; Australia................................................... Rheotanytarsus flabellatus Glover, 1973 View in CoL

- Inferior volsella not apically pointed, superior volsella elongated with bluntly rounded apex; median volsella with relatively narrow, ovoid apical plate; Thailand................................. Rheotanytarsus thailandensis Moubayed, 1990 View in CoL

3. Median volsella with distal setae fused into narrow plate with or without apical points; Japan........................................................................................ Rheotanytarsus yufualbus Sasa & Suzuki, 1991 View in CoL

-. Median volsella with lamelliform setae, but never fused into plate............................................... 4

4. AR relatively large and about 0.75; superior volsella with microtrichia; Europe, north Africa, Canada, America, Mongolia..................................................................... Rheotanytarsus pellucidus ( Walker, 1848) View in CoL

- AR relatively small and less than 0.60; superior volsella without microtrichia...................................... 5

5. Superior volsella with knob-like structure; stem of median volsella apically broader................................ 6

- Superior volsella without knob-like structure; stem of median volsella tapered or with equal width..................... 7

6. Gonostylus curved apically; anal crest nearly parallel-sided; tergite IX triangular... Rheotanytarsus pinderi Yao & Liu View in CoL sp. n.

- Gonostylus not curved apically; anal crest of V-type; tergite IX with rounded margin; Australia, China, Thailand................................................................................... Rheotanytarsus oss Cranston, 1997 View in CoL

7. Anal crest basally fused to form an arc.................................... Rheotanytarsus tamasecundus Sasa, 1980 View in CoL

- Anal crest basally not fused............................................................................. 8

8. Anal point very thin apically; anal crest reduced and not visible; China........ Rheotanytarsus apiculus Wang & Guo, 2004 View in CoL

- Anal point not thin apically; anal crest visible and evenly developed............................................. 9

9. Inferior volsella without microtrichia; cell m with about 20 setae; Ghana, China.................................................................................................. Rheotanytarsus buculicaudus Kyerematen, 2000 View in CoL

- Inferior volsella with microtrichia; setae number of cell m less than 5........................................... 10

10. Thorax pale or pale brown without spots; Thailand.......................................................... 11

- Thorax pale yellow with dark brown spots and postnotum dark brown; China..................................... 12

11. Anal tergal bands nearly horizontal; 13th flagellomere of antenna extremely short, AR only 0.06...................................................................................... Rheotanytarsus minusculus Kyerematen, 2000 View in CoL

- Anal tergal bands of V-type; 13th flagellomere of antenna relatively long, AR 0.39–0.48........................................................................................ Rheotanytarsus contrerasi Andersen & Saether, 2000 View in CoL

12. Anal tergal bands fused; stem of median volsella with foliate setae basally; gonostylus with rounded apex................................................................................ Rheotanytarsus vallenduuki Yao & Liu View in CoL sp. n.

- Anal tergal bands separated; stem of median volsella without foliate setae; gonostylus with pointed apex...................................................................................... Rheotanytarsus ashei Yao & Liu View in CoL sp. n.