Silba
Creators: name: Macgowan, Iain
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Lonchaeidae
Silba

description: Key to males of Silba admirabilis species group
(all Afrotropical unless indicated)
1. Phallus boat-shaped, basal plate fused laterally to phallus, basiphallus spiculate (Figs. 33–34)....................................................................................................... chalkei McAlpine; S.E. Asia.
- Phallus with a distinct ventrally situated basal plate.......................................................... 2
2. Phallus with an additional pair of processes between it and the basal plate (Figs. 29–30)................................................................................................. admirabilis McAlpine; India & Sri Lanka.
- Phallus without such additional processes.................................................................. 3
3. Basiphallus with an obvious bulge on inner surface, in anterior view basal plate of phallus simple and lanceolate. (Figs. 35–36)......................................................................... flavitarsis MacGowan; S.E. Asia.
- Basiphallus without such a bulge or lanceolate basal plate..................................................... 4
4. In ventral view basal plate of phallus diamond shaped (Figs. 16 & 18)............................................ 5
- In ventral view basal plate of phallus not diamond shaped...................................................... 6
5. Basal plate serrated apically and laterally, apical excavation a narrow V-shape (Figs. 15–16)................................................................................................................ lubumbashi sp. nov.
- Basal plate without marginal serrations, apical excavation broader, U-shaped (Figs. 17–18)................ mbuti sp. nov.
6. In ventral view basal plate of phallus with apical margin only slightly concave, without a large V or U-shaped excavation (Figs. 8, 26, 38 &42).................................................................................. 7
- Basal plate of phallus at apex with an obvious V or U-shaped excavation........................................ 10
7. Basal plate long and very narrow, without any marginal serrations or spicules. (Fig. 8)................... bredoi sp. nov.
- Basal plate wider, often with marginal serrations or spicules. (Figs. 26, 38 &42).................................. 8
8. Basal plate shorter than phallus, thin and translucent, with serrated margins, basiphallus broad and setulose (Figs. 37 & 38)................................................................................. hilli (Malloch); Australasia
- Basal plate as long or longer than phallus. (Figs. 26 –42)...................................................... 9
9. Apical margin of basal plate strongly serrated (Fig. 26).......................................... upemba sp. nov.
- Apical margin of basal plate almost smooth, with only a few spicules (Fig. 42).................... namibia MacGowan
10. In ventral view basal plate of phallus markedly swollen medially, apex with two diverging processes with between them an open U-shaped excavation (Fig 24)............................................................. tekei sp. nov.
- In ventral view basal plate of phallus not markedly swollen medially........................................... 11
11. Basal plate of phallus bearing spicules across its ventral surface (Figs 22 & 32)................................... 12
- Basal plate of phallus without spicules across its ventral surface................................................ 13
12. Basal plate covered in large spicules, apically with a large open V-shaped excavation (Figs. 31–32).... apodesma McAlpine
- Basal plate bearing only small spicules, mostly along margins, apically with a U-shaped excavation (Figs 21–22)................................................................................................ spiculata sp. nov.
13. In ventral view basal plate of phallus narrow, with a spanner-shaped apex (Figs. 9–10)................. garamba sp. nov.
- In ventral view basal plate of phallus usually broader, without such a spanner-shaped apex.......................... 14
14. In ventral view basal plate of phallus apically split for almost half of its length (Figs. 20 & 28)...................... 15
- In ventral view basal plate of phallus without such a deep split............................................... 16
15. Basal plate of phallus with two thin leaf-like parallel, gradually tapering, bluntly pointed apical lobes (Figs. 27–28)................................................................................................. wittei sp. nov.
- Basal plate of phallus with parallel apical lobes constricted near apex, in lateral view with expanded apex. (Figs. 19–20)............................................................................................ saegeri sp. nov.
16. In ventral view basal plate of phallus with two square-ended apical processes separated by a V-shaped excavation. (Figs. 39– 40).................................................................. israel MacGowan and Freidberg; Israel.
- Basal plate of phallus without square ended apical processes.................................................. 17
17. In lateral view basiphallus very broad and rounded (Fig. 11). In ventral view basal plate widening at apex, forming two rather narrow, lateral apical processes separated by a wide apical excavation (Fig. 12)....................... hambai sp. nov.
- In lateral view basiphallus not greatly broadened (Figs. 3, 5, 13 & 43).......................................... 18
18. In ventral view basal plate widening steadily from base to apex, apical processes almost parallel sided, apical excavation a rel- atively wide U-shape (Figs. 3–4)............................................................ bakongo sp. nov.
- In ventral view basal plate broadest before the apex or straight sided (Figs. 6, 14 & 44)............................ 19
19. In ventral view basal plate parallel sided, apex with two pointed processes divided by a U-shaped excavation (Figs. 43–44)................................................................................... pappi Soós; Afghanistan
- In ventral view basal plate not parallel sided, broadest before the apex (Figs. 6 & 14).............................. 20
20. Basal plate broadened apically, in ventral view widest at apical third, apical processes slightly bulbous at apex, apical excavation a narrow mouthed U-shape, basiphallus not swollen. (Figs. 5–6)................................ boulangi sp. nov.
- Basal plate thin and translucent, in ventral view at apical quarter before narrowing to apex with a V-shaped apical excavation, in ventral view basiphallus slightly swollen (Figs. 13–14)......................................... inimvua sp. nov.
description: Published as part of Macgowan, Iain, 2015, A review of the Silba admirabilis McAlpine species group (Diptera: Lonchaeidae) with descriptions of thirteen new species from the Afrotropical region, pp. 515-534 in Zootaxa 4032 (5) on pages 533-534, DOI: 10.11646/zootaxa.4032.5.3, http://zenodo.org/record/232754