Systropus

Cui, Weina & Yang, Ding, 2010, Two new species and two new synonyms of Systropus Wiedemann, 1820 from Palaearctic China (Diptera: Bombyliidae), Zootaxa 2619, pp. 14-26 : 14-15

Key to species of genus Systropus from Palaearctic China

1. Yellow midlateral spot on mesoscutum present............................................................................................................ 2

- Yellow midlateral spot on mesoscutum absent........................................................................................................... 18

2. Anterolateral spot on mesoscutum connected with midlateral spot by wide yellow band........................................... 3

- Anterolateral spot on mesoscutum connected with midlateral spot by slender yellow band or anterolateral spot and midlateral spot isolated ............................................................................................................................................... 10

3. Metasternum yellow with two pairs of black spots, of which the anterior pair is elongated ....................................... 4

- Metasternum black except anterior part with a V-shaped yellow pattern..................................................................... 5

4. Antennal scape pale yellow or with brown apex, pedicel and first flagellomere black; hind tibia black except basal portion and apex, first tarsomere yellow except apical portion black, second to fifth tarsomeres black; scutellum black with yellow triangular posterior border..................................................................................... S. luridus Zaitzev

- Antenna entirely black; hind leg black except apical portion of tibia and basal portion of first tarsomere; scutellum black with yellow posterior border ................................................................................ S. changbaishanus Du & Yang

5. Midlateral spot of mesoscutum connected with posterolateral spot by yellow or yellowish brown wide band .......... 6

- Midlateral spot of mesoscutum connected with posterolateral spot by yellow line or midlateral spot and posterolat- eral spot isolated ........................................................................................................................................................... 7

6. Antennal ratio 2.5: 1: 2; hind first to third tarsomeres yellow, fourth and fifth tarsomeres black; abdomen brown, tergites 2–5 with dark brown mid-longitudinal stripes .................................................................... S. submixtus Séguy

- Antennal ratio 2.25: 1: 1.25; hind first and second tarsomeres yellow, third to fifth tarsomeres black; abdomen dark brown, tergites 2–5 without dark brown mid-longitudinal stripes ..................................... S. ganquananus Du & Yang

7. Antennal scape and pedicel yellow, first flagellomere black; hind first tarsomere yellow, second to fifth tarsomeres black .................................................................................................................................................. S. brochus sp. nov.

- Antennal scape yellow or black, pedicel and first flagellomere black ......................................................................... 8

8. Antennal scape entirely pale yellow ................................................................................................. S. fadillus (Séguy)

- Antennal scape entirely black or partly brown ............................................................................................................. 9

9. Antenna black except scape brown at base, antennal ratio 2.75: 1: 2.75; hind trochanter and femur brown, tibia yel- lowish brown except apical portion, tarsus black ...................................................................... S. limbatus (Enderlein)

- Antenna entirely black, antennal ratio 3.25: 1: 2; hind trochanter yellowish brown, femur yellow, tibia brown except basal and apical portions yellow, first and second tarsomeres yellow except apical portion of second tarsom- ere, third to fifth tarsomeres dark brown to black .................................................................. S. kangxianus Du & Yang

10. Metasternum yellow with one or two pairs of black spots ......................................................................................... 11

- Metasternum black except anterior part with a V-shaped yellow pattern................................................................... 17

11. Petiolus formed from abdominal segments 2–3 and anterior part of segment 4 ........................................................ 12

- Petiolus formed from abdominal segments 2–4 and anterior part of segment 5 ........................................................13

12. Posterolateral spots on mesoscutum transversely coalesced .............................................. S . curtipetiolus Du & Yang

- Posterolateral spots on mesoscutum not transversely coalesced .................................................. S. perniger Evenhuis

13. Metasternum with a black wide stripe on both sides .................................................................................................. 14

- Metasternum with two pairs of black spots, of which the anterior pair is elongated with the anterior portion not coalesced ............................................................................................................................ S. daiyunshanus Yang & Du

14. Apex of hind tibia and entire tarsus black ...................................................................................... S. excisus Enderlein

- Apex of hind tibia yellow, tarsus entirely black or partly yellow............................................................................... 15

15. Antennal scape yellow; body length shorter than 18 mm ............................................................. S. tricuspidatus Yang

- Antennal scape yellowish brown or darker; body length longer than 20 mm ............................................................ 16

16. Metasternum with a wide black stripe on both sides, sometimes joining at base; median epiphallic lobe divided into two log-like blackened lobes at apex, and paired, log-like lateral epiphallic lobes blackened at apex .......................... ....................................................................................................................................................... S. hoppo Matsumura

- Metasternum with a wide black stripe on both sides which join at basal 1/6 of metasternum; median epiphallic lobe tapering apically, paired lateral epiphallic lobes absent .................................................................... S. coalitus sp. nov.

17. Antennal scape yellowish brown or darker, pedicel and first flagellomere black; hind tarsus black except basal half of first tarsomere yellow ......................................................................................................... S. henanus Yang & Yang

- Antennal scape and pedicel yellow, first flagellomere black; hind tarsus yellow to yellowish brown .......................... ................................................................................................................................................ S. flavicornis (Enderlein)

18. Propleuron black ..................................................................................................................... S. gansuanus Du & Yang

- Propleuron yellow....................................................................................................................................................... 19

19. Antenna black except scape yellow at base; antennal ratio 2.5: 1: 1.5; hind tibia black except apical portion; metasternum dark blue to black except anterior part with a V-shaped yellow pattern; wing normal in shape............... ........................................................................................................................................................... S. chinensis Bezzi

- Antenna entirely black; antennal ratio 2.5: 1: 2.1; hind tibia black except basal and apical portions yellow; metasternum dark brown to black without yellow pattern; wing widened .................................... S . thyriptilotus Yang