Rhabdogaster oresbios, Londt, 2006

Londt, Jason G. H., 2006, A review of the Afrotropical genus Rhabdogaster Loew, 1858 with descriptions of new species (Diptera: Asilidae: Stenopogoninae), African Invertebrates 47, pp. 243-313 : 272-274

Rhabdogaster oresbios sp. n.

Figs 5 , 77–79 , 129

Etymology: From Greek oresbios (living on mountains). Refers to the habitat in which the species is usually found.

Description: Based mainly on holotype ơ.

Head: Black, silver-gold pruinose, pale yellow setose.Antenna dark red-brown to black, setae pale yellow. Face pruinose except for central shiny black apruinose area. Mystax entirely pale yellow, occupying approx. lower two-thirds of face. Frons and vertex entirely apruinose (including ocellar tubercle). Occiput entirely gold-silver pruinose. Proboscis and palpi dark red-brown, setae pale yellow.

Thorax: Black, silver-gold pruinose, long pale yellow setose. Mesonotum largely apruinose (including postpronotal and postalar lobes), pruinescence limited to narrow lateral and posterior margins. Pleura extensively pruinose except for small apruinose areas on an- and katepisternum. Scutellum almost entirely apruinose (has narrow anterior pruinose margin), with approx. 20 fine, long sctl s. Postmetacoxal bridge entirely goldsilver pruinose. Legs: cx dark red-brown, gold-silver pruinose, pale yellow setose; troc dark red-brown, long pale-yellow setose; fem dark red-brown except for arrange parts as follows – posterior surface of leg 1, proximodorsal parts of legs 2 and 3, long, pale yellow setose; tib dark red-brown with just proximal end orange, long pale yellow setose (a black setal comb ventrodistally); tar dark red-brown, partly pale yellow (mainly dorsally) and black (mainly ventrally) setose. Wing ( Fig. 5 ) 5.0 x 2.0 mm, veins yellow anteriorly, light-brown posteriorly, membrane transparent, unstained, entirely orange and brown microtrichose. Discal and costal cells entirely microtrichose.

Abdomen: Black, silver-gold pruinose, pale yellow setose. Tergites almost entirely apruinose with narrow pruinose margins, setae tiny except along lateral margins where they are long, pale yellow. Sternites entirely pruinose, long pale yellow setose.Terminalia ( Figs 77– 79 paratype): epand in lateral view longer than external lobes of goncx and hypd, tapering to middle before gradually diverging to fairly broadly-rounded tips (the tips have thin fairly transparent bordering ‘flages’); in dorsal view lobes very narrowly joined proximomedially; hypd in lateral view curved, with strongly upcurved distal region, longer than external lobe of goncx, but shorter than epand; in ventral view broadly-rounded proximally, tapering rapidly to moderately long, narrow, parallel-sided process with rounded apex. In lateral view external lobe of goncx and gonst hardly visible.

Variation: A remarkably consistent species with little individual variation.

Holotype: ơ SOUTH AFRICA: KwaZulu-Natal: ‘ South Africa: Natal / Cathedral Peak area / 2829 Cc 16– 18.xii.1977 / JGH Londt ex Malaise’.

Paratypes: SOUTH AFRICA: KwaZulu-Natal: 1ơ ‘ South Africa KZN / Royal Natal N. Park 1425m / 28 ° 41.362'S 28 ° 56.327'E / Malaise tr., stream y-wood [Yellowwood or Podacarpus] / Date : 10–13.xii.2004 / Coll: M. Mostovski’; 2^‘ South Africa: Natal / Royal Natal National / Park 6–10.xii.1984 / JGH Londt Riverine / bush Montane slopes’; 3ơ 6^same data as holotype; 1^‘ South Africa: Natal / Cathedral Peak area / 26–27.xii.1977 . 2829CC / R.M. Miller, indigenous / for., Malaise trap.’; 1ơ ‘ South Africa: Natal / Cathedral Peak: / Indumeni gorge 2829CC / 14–18.xi.1982 / D.A. Barraclough’; 1ơ 12^‘ South Africa. Natal / Ukhahlamba Res. Stn. / 2829CC 13.i.1984 / Themeda veld / P. Reavell’; 3ơ ‘ S. Africa. Natal / 2, 5 km S. Ukuhlamba / Res. Station . Grassy margin / path to weir. 2829CC / 21 Dec. 1979 . B. Lamoral’; 1ơ 4^‘ RSA: KZ-Natal #86 / Culfargie / 28 ° 48'S: 29 ° 35'E 1316 / Date : 2–3.xii.1994 / Coll: D.A. Barraclough’; 5ơ 5^‘R. S.A.: KZ-Natal #115 / Monks Cowl Nature Res. / 29 ° 03'S: 29 ° 24'E 1440m / Date : 10.xii.1995 / Coll: J.G.H. Londt / Stream & Forest edges’; 7ơ 3^‘ South Africa: Natal / Injasuti Nature Res. / 2929AB 5– 11.xii.1983 / Coll: J.G.H. Londt / at M/V light trap.’; 3ơ ‘ South Africa: Natal / Giant’s Castle Game / Res. – Injasuti area / SE2929AB JGH Londt / 5–11.xii.1983 ’; 1ơ 1^‘ South Africa: Natal / Giants Castle G. Res / 2929AD 16.ii.1983 / D. Barraclough / Montane grassland’; 1ơ 1^‘ Karkloof range / nr. Mt Alida [2911S:3020E] / Natal, S. Africa / B. & P. Stuckenberg / 24.xii.1961 ’; 1^‘ South Africa: Natal / Karkloof Geekies farm [2915S:3020E] / 12.xii.1978 / J.G.H. Londt’; 1^‘ RSA: Natal #113 / Chakas Rock / 29 –

32'S:31–15'E 160m / Date : 9–16.vi.1995 / Coll: J.G.H. Londt / Chakas Rock Chalets area’; Eastern Cape: 1ơ ‘ S Africa: E Cape #2 / 37 km NE Maclear / 30 ° 53'S : 28 ° 18'E 1670m / Date : 3.ii.1992 Natal / Museum Expedition / Grassland and stream.’; 1ơ ‘Sth Africa Cape Prov / Ca. 16 km NE. Hogsback / on Cathcart Road. / 3226BD. 19.i.1984 / D. & C. Barraclough. / Rocky hillside .’.

Distribution, phenology and biology (Tables 1, 2, Fig. 129 ): Recorded only from South Africa. Collected mainly in higher altitude areas, and found mainly during summer (November – February), but there is an isolated record in June associated with a coastal locality.

Similar species: R. lindneri sp. n., major and xanthokelis sp. n.

Figures

Figs 1–5. Rhabdogaster species: (1–3) R. pedion sp. n., Normandien Forest: (1) entire male, (2) sclerotised postmetacoxal bridge, (3) wing venation; (4) R. maculipennis Engel, 1929, lectotype, male wing showing pattern of staining; (5) R. oresbios sp. n., wing showing dark appearance caused by dark microtrichia.

Figs 68–79. Rhabdogaster species, male terminalia: (68–70) R. nuda Loew, 1858, Stellenbosch: (68) lateral, (69) dorsal, (70) ventral; (71–73) R. nyx sp. n., Gt. Winterhoek holotype: (71) lateral, (72) dorsal, (73) ventral; (74–76) R.oldroydi (Lindner, 1973), Fish River: (74) lateral, (75) dorsal, (76) ventral; (77–79) R. oresbios sp. n., Cathedral Peak paratype: (77) lateral, (78) dorsal, (79) ventral. Scale bars = 1 mm.

Fig. 129. Distribution of Rhabdogaster species: oldroydi (Lindner, 1973) – closed circles; oresbios sp. n. – open circles; pellos sp. n. – closed squares; poa sp. n. – open squares.