Sciomyzidae

Knutson, Lloyd V., Deeming, John C. & Ebejer, Martin J., 2018, The Snail-killing Flies (Diptera: Sciomyzidae) of West Africa, Zootaxa 4483 (1), pp. 67-100 : 69-70

Key to species of West African Sciomyzidae

1. Propleural seta present ( Sciomyzinae , Sciomyzini )........................................................... 2

- Propleural seta absent (a few minute setulae may be present) ( Sciomyzinae , Tetanocerini )............................ 5

2. Arista with or without setalike dorsobasal setulae; frons pruinose or shiny brownish black; wing unmarked or with a few large darker spots; anal vein reaching or not reaching margin of wing................................................ 3

- Arista without setalike dorsobasal setulae; frons mostly pruinose yellowish to brownish; wing densely patterned; anal vein distinctly reaching margin of wing............................................ ( Pherbellia , subgenus Graphomyzina )

3. Arista with setalike dorsobasal setulae; frons pruinose black; anal vein not reaching margin of wing.................................................................................. Colobaea occidentalis Knutson & Deeming n. sp.

- Arista without setalike dorsobasal setulae; frons shiny brownish black; anal vein reaching margin as a fold............................................................................... Pteromicra zariae Knutson & Deeming n. sp.

4. Marginal cell of wing with 2–5 brown spots; anterior surstylus broadly triangular, with 4 marginal lobes; posterior surstylus very long, curved, truncate apically................................... Pherbellia (Graphomyzina) kivuana Verbeke

- Marginal cell of wing entirely infuscated; anterior surstylus a rectangular sclerite; posterior surstylus relatively short, acuminate apically....................................................... Pherbellia (Graphomyzina) costata Verbeke

5. Midfrontal stripe well developed (linear, shiny blackish brown), bordered by broad pruinose yellow areas; wing with reticulate pattern......................................................................... Ethiolimnia zumpti Verbeke

- Without a linear midfrontal stripe, frons often concave, entirely pruinose or shiny to subshiny with pruinosity limited to orbital.................................................................................................... 6

6. Two pairs of fronto-orbital setae, anterior pair proclinate, posterior pair reclinate (♂) or fronto-orbital setae absent or weak (♀); lunule very large, markedly inflated............................................... Sepedoninus curvisetis Verbeke

- Only posterior fronto-orbital setae present; lunule not markedly inflated.......................................... 7

7. Postocellar setae absent ( Sepedonella ).....................................................................8

- Postocellar setae present ( Sepedon )....................................................................... 9

8. Frons shiny, very weakly pruinose on margin of anterior third, on a broad median line and narrowly, but more densely, on eye margin; thorax bluish black throughout, with pleura predominantly whitish pruinose; femora yellowish, hind femur with reddish annulus (sometimes incomplete) at apical third...................................... Sepedonella nana Verbeke

- Frons with broad, velvety, black mark on anterior portion extending along eye margin; thorax chestnut-coloured, sometimes infuscate dorsally; hind femur lacking annulus........................ Sepedonella castanea Knutson & Deeming n. sp.

9. Presutural seta (situated behind postpronotal lobe and between notopleural area and dorsocentral row) well developed (if weak, scutum yellowish brown, not bluish to greyish black), and antennal scape at least twice as long as wide................ 10

- Presutural seta weak or absent; scutum yellowish, brownish or bluish to greyish black; antennal scape not longer than wide..................................................................................................... 12

10. Scutum yellowish brown; lower face strongly projecting (Fig. 26); antennal scape almost 3 times as long as wide............................................................................... Sepedon (Sepedomyia) nasuta Verbeke

- Scutum bluish to greyish black; lower face not strongly projecting; antennal scape short, about as long as wide.......... 11

11. Face black with silvery white pruinosity, except for pair of yellow spots below antennae in some specimens, posterior portion of gena yellow with strong white pruinosity, anterior portion shiny black, lunular area yellow; fore and mid femora usually entirely yellow, or occasionally slightly darkened apicodorsally; hind femur yellow in apical half except for narrow black dorsal stripe and black apical annulus; all tibiae black except mid tibia occasionally brownish; male postabdomen (Fig. 10), aedeagus hook-like apically............................................... Sepedon (Parasepedon) ornatifrons Adams (including the probable synonym S. (P). maculifemur Verbeke )

- Face entirely black; gena mostly shiny black, narrowly yellow posteroventrally fore and mid femora blackish on dorsal surface; hind femur black in apical half except for pre-apical yellow spot on anterior and posterior surface, or with yellow preapical annulus; male surstylus and aedeagus (Figs 20, 21)....................... Sepedon (Parasepedon) umbrosa Verbeke

12. Scutum yellowish or brownish.......................................................................... 13

- Scutum bluish or blackish, occasionally brownish laterally, especially the postpronotal angle........................ 14

- Large yellowish to brownish species with 1 pair of very large black parafrontal spots on completely shiny frons.............................................................................. Sepedon (Parasepedon) straeleni Verbeke

14. Female with faintly developed, velvety, linear, whitish parafrontal spots; male parafrontal spots narrowly blackish on inner margin; head yellowish................................................................................ 15

- Female and male with well-developed, velvety black and white parafrontal spots; head brownish to black.............. 16

15. Male postabdomen (Fig. 13); face subshiny yellow; thorax bluish-black; abdomen yellow to brownish....................................................................................... Sepedon (Parasepedon) ruficeps Becker (possible synonym of S. (P.) senegalensis Macquart )

- Male aedeagus and surstylus, (Figs 11, 12); face yellow pruinose; thorax black...... Sepedon (Parasepedon) neavei Steyskal

16. Small black portion of parafrontal spots oval to rounded, usually not separated posteriorly from eye margin by small whitish pruinosity; frons and fronto-orbital spot usually shiny black; aedeagus and postabdomen (Figs 16, 19) in lateral view, aedeagus with deep incision above ciliate apex, apex not strongly reflexed........... Sepedon (Parasepedon) trichrooscelis Speiser (including the probable synonym S. (P.) lippensi Verbeke )

- Small black portion of parafrontal spots oval, usually entirely separate from eye margin; frons usually partly yellowish brown; male aedeagus and postabdomen, (Figs 15, 17, 18) in lateral view, aedeagus not incised above ciliate apex, apex strongly reflexed................................................ Sepedon (Parasepedon) hispanica ruhengeriensis Verbeke