Oligopogon nigripennis Engel & Cuthbertson, 1937

Londt, Jason G. H., 2014, A revision of Afrotropical Oligopogon Loew, 1847 (Diptera: Asilidae) with the description of eighteen new species, African Invertebrates 55 (2), pp. 269-269 : 298-299

Oligopogon nigripennis Engel & Cuthbertson, 1937

Oligopogon nigripennis Engel & Cuthbertson, 1937: 14–15 (fig. 9b antenna); Hull 1960: 212; Hull 1967: 238 (record); Oldroyd 1970: 295 (key); 1974: 123 (key); Oldroyd 1980: 370 (catalogue).

Redescription:

Head: Dark red-brown, silver pruinose, dark red-brown and pale yellow setose.Antenna: Red-brown except for narrow orange-brown proximal end of postpedicel. Segmental ratios: 1: 1.0: 3.8:1.6 (scape, pedicel, postpedicel, style). Scape and pedicel of similar length, red-brown setose. Postpedicel laterally compressed in cross-section, tapering slightly distally. Style smaller in diameter to distal end of postpedicel, equipped with long red-brown setae distally (as illustrated by Engel and Cuthbertson (1937) – fig. 9b – some setae may have been broken off). Face, frons and vertex silver pruinose, mystax red-brown, ocellar macrosetae not evident. Occiput uniformly silver pruinose (See Fig. 2A), red-brown setose dorsally, pale yellow-white ventrally. Face to head width ratio in anterior view 1:4.9 (face much narrower than one eye). Proboscis short red-brown, straight, pale yellowish setose. Palpi minute, 2-segmented.

Thorax: Red-brown with paler parts, extensively silver and red-gold pruinose, red-brown and pale yellow setose. Mesonotum: Dark red-brown except for orange-brown postpronotal and postalar lobes, fairly uniformly pruinose except for postpronotal lobes and narrow strip between them. Macrosetae red-brown, poorly developed, 2 npl, 1 spal, 1pa, general setae short red-brown. Scutellum red-brown, extensively apruinose except for tiny lateral areas, fine red-brown setose. Pleura patchy red-brown and orange-brown, fairly uniformly silver pruinose.Anepimeron fine pale yellow setose, katatergal setae long pale yellow. Legs: Coxae orange-brown, silver pruinose, pale yellow setose.Trochanters orange-brown, pale yellow setose. Femora orange-brown, red-brown dorsally, pale yellowish setose. Tibiae red-brown, paler orange-brown proximally, yellow setose. Tarsi red-brown, yellow setose. Wings ( Fig. 7): 5.8 × 2.3mm. Membrane extensively microtrichose (although weakly in places), extensively pale brownish stained.

Abdomen: Terga shiny dark red-brown, posterior margins of terga orange-brown, entirely apruinose, entirely yellowish setose. Sterna dark red-brown, entirely gold-silver pruinose, pale yellow setose. Terminalia missing (Note: They may have been removed and mounted on a slide).

Type material: ZIMBABWE: 1♂ ‘ Type von / Oligopogon / nigripennis / Engel’ [orange], ‘J.E. Drysdale / collector’, ‘ 5,500 ft / Vumba Mts. [19°53'S 31°22'E], S. Rhodesia, / 20.x.1935 ’, ‘971 [accession number]’ (NMBZ).

Note: The specimen is missing the distal ½ of the left wing and the abdominal segments beyond segment 5. Other material examined: Hull (1967: 238) recorded nigripennis from Basutoland (= Lesotho) based on 1♀, lacking antennae, labelled ‘Mamalapi Mtn, 27.12.1948 (C. Jacot-Guillarmod)’. This specimen was identified by Dr S. W. Bromley and is in AMGS. Interestingly enough he went on to describe a new Holopogon Loew, 1847 (i.e. niveoscutum ) based on 1♂ with identical label data on the very next page (239). This species was subsequently transferred to Ischiolobos Londt, 2005 (Londt 2005) . I have now studied the Mamalapi female, as well as a series of specimens in the DMSA and USNM from ‘Little Bokong R. / Basutoland / 4 Jan 1947 / L. Bevis’ also identified by Bromley, in 1949, as nigripennis which should also be assigned to

Ischiolobos niveoscutum (Hull, 1967) . Based on this evidence it cannot be accepted that nigripennis is to be found in Lesotho.

Distribution ( Table 1), phenology (Table 2) and biology: Known only from the type locality in eastern Zimbabwe. Collected in October. Details of the habitat are not known but the darkish wings suggest a forest margin species.