Rhabdogaster melas, 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 : 267

Rhabdogaster melas sp. n.

Figs 59–61

Etymology: From Greek melas (black, dark). Refers to the generally dark appearance of this species (one of only a few with a predominantly black mystax).

Description: Based on holotype ơ.

Head: Black, silver pruinose, black and white setose. Antenna black, setae black. Face with large centrally situated apruinose area. Mystax predominantly black (few white setae), occupying approx. lower half of face. Frons and vertex entirely apruinose, white and black setose. Occiput entirely pruinose, white setose. Proboscis and palpi dark redbrown, setae white.

Thorax: Dark red-brown to black, silver pruinose, mainly white setose. Mesonotum extensively apruinose except for narrow lateral and posterior margins. Pleura largely pruinose except for big apruinose spot on anepisternum and small spots on katepisternum and anepimeron. Scutellum extensively apruinose except for hind margin, with 2 moderately developed sctl s accompanied by approx. 8 minor setae. Postmetacoxal bridge entirely gold-silver pruinose. Legs: cx dark red-brown, silver pruinose, white setose; troc dark red-brown and orange-brown; fem dark red-brown with orange-brown dorsal surfaces, white and black setose (a few black ventral macrosetae present); tib dark red-brown with orange-brown dorsoproximal parts, black and white setose; tar dark red-brown, setae black and white. Wing 4.7 x 1.8 mm, veins dark brown, membrane largely transparent, slightly orange stained, almost entirely microtrichose (except for small proximal parts). Discal and costal cells entirely microtrichose.

Abdomen: Black, silver-gold pruinose, white setose. Tergites largely apruinose except for narrow lateral margins, setae short medially, longer laterally. Sternites entirely pruinose, setae moderately long. Terminalia ( Figs 59–61 ) not as well sclerotised as preceding segments: epand in lateral view slightly longer than external lobe of goncx, tapering to broadlyrounded tips; in dorsal view lobes narrowly joined proximomedially; hypd in lateral view curved, shorter than both external lobe of goncx and epand; in ventral view broadly-rounded proximally, tapering rapidly to long, narrow, parallel-sided process with truncate apex. In lateral view external lobe of goncx and gonst hardly visible.

Holotype: ơ SOUTH AFRICA: KwaZulu-Natal: ‘ Fire lookout / Grassland on / steep slopes / 7500–7700ft’, ‘ Cathedral Peak [3319CC] / Forestry Reserve / Natal Drakensberg / March 1959 / B.R. & P.J. Struckenberg’.

Paratypes: SOUTH AFRICA: KwaZulu-Natal: 2^same data as holotype; 1^‘ Alpine meadows alti- / tude 8500–9700 ft. ’, ‘ S. Afr. Natal, Drakens- / berg. Cathedral Peak / area, 19–23.iii.1955 / coll. G. Rudebeck’ ( MZLU) .

Distribution, phenology and biology (Tables 1, 2): Known from two collections in the Cathedral Peak area, South Africa, where specimens were captured in high altitude montane grassland in March (late summer).

Similar species: R. nyx sp. n.

Figures

Figs 55–67. Rhabdogaster species, male terminalia: (55–58) R. major Oldroyd, 1970, damaged Mt Ndogo holotype: (55) lateral (left side), (56) dorsal, (57) ventral, (58) lateral (right side); (59–61) R. melas sp. n., Cathedral Peak holotype: (59) lateral, (60) dorsal, (61) ventral; (62–64) R. nitida Hull, 1967, Royal Natal Nat. Park: (62) lateral, (63) dorsal, (64) ventral; (65–67) R. nuda Loew, 1858, ‘Cap. B. Sp.’ holotype: (65) lateral, (66) dorsal, (67) ventral. Scale bars = 1 mm.