Acnephalomyia dorsalis ( Macquart, 1838 ) Londt, 2010

Londt, Jason G. H., 2010, A review of Afrotropical Acnephalum Macquart, 1838, including the reinstatement of Sporadothrix Hermann, 1907 and descriptions of two new genera (Diptera: Asilidae: Stenopogoninae), African Invertebrates 51 (2), pp. 431-431 : 448-451

Acnephalomyia dorsalis ( Macquart, 1838) comb. n.

Figs 35–37 , 66

Acnephalum dorsale: Macquart 1838: 52 (fig. 4 whole fly) [1839: 168]; Kertesz 1909: 88 (catalogue); Curran

1934: 5; Hull 1962: 192; Oldroyd 1974: 27; 1981: 359 (catalogue).

Redescription (Based on lectotype. Condition: Good; dirty and covered with some fungal strands.Anterior pleurites of left side somewhat damaged (probably by a dermestid) and the right mesothoracic leg stuck into position with glue. The specimen is double mounted with tip of abdomen touching card.):

Head: Dark red-brown to black, white setose, silver pruinose (evident mainly on frons). Antenna: Scape and pedicel brown-orange, postpedicel and style dark red-brown. Segmental ratios 1.0:1.2:4.4:0.4:1.8 (dirt makes measurements difficult) – scape and pedicel subequal in length, white setose; setae of pedicel as long or longer than postpedicel; postpedicel twice as long as scape and pedicel combined; style 2- segmented, tipped with spine, subequal in length to scape and pedicel combined. Face dark red-brown to black, mystax fine white, covering entire face. Frons, vertex and postocular region dark red-brown to black, long white setose; angle subtended by eye margins at level of frons/vertex c. 12°. Proboscis orange-brown to dark red-brown, white setose, slightly downturned distally. Palpus 2-segmented, white setose.

Thorax: Dark red­brown to black. Pronotum mostly fine white setose, but with transverse row of long, pale yellowish macrosetae. Mesonotum white setose. Lateral macrosetae moderately well developed, translucent white (5 or 6 npl, c. 5 spal, c. 5 pal). Pleura largely asetose except for numerous, long, white katatergals and dorsally situated anepisternals. Katepisternum asetose. Scutellum shiny black apruinose with moderately developed transverse, subapical groove. About 8 moderately developed, whitish apical macrosetae accompanied by slightly shorter, fine, white setae; disc white setose. Legs: Mostly brown-orange, but parts of fem dark red-brown dorsally.

Major setae erect, minor setae recumbent, white. Ventral parts of tar and terminal end of tib have short, black setae. Claws black, empodia slender, yellowish, about threequarters length of claws; pulvilli tiny (about one-quarter length of claws). Haltere pale yellow, base slightly darker. Wing: 5.7× 2.4 mm. Veins brown, membrane lacking microtrichiae. Membrane transparent, slightly orange stained proximally. Vein C extends around wing margin, terminating at A 1, R 4 with small basal stump-vein, cell m 3 open.

Abdomen: Terga clearly broader than long, mostly dark red-brown to black, but orange-brown laterally. Orange-brown colour extends a short distance along posterior margins of terga. Terga apruinose, entire abdomen covered with longish white setae (weakly so anteromedially). Sterna red-brown, white setose. Terminalia largely withdrawn between T6 and S6 and obscured by setae. Genitalia (male from Knersvlakte, north of Vanrhynsdorp, Figs 35–37 ): Epand reduced (much shorter than goncx), distally broadly rounded (not incised medially to form distinct lobes). Proc juts out well beyond level achieved by epand (lateral view). Exterior lobe of goncx suboval (lateral view), distally pointed; interior lobe longish, slightly downturned distally. Hypd broadly rounded basally, somewhat incised mid­laterally and with long medial, finger­like distal lobe.

Lectotype: SOUTH AFRICA: ♂ ‘Syn­ / type’ [circular blue­rimmed label], ‘ Acnephalum / dorsale / 185 in / Coll. / Bigot.’, ‘Coll. Bigot. / abt. 1845–93. / Pres. 1913 by / J.E. Collin.’ (OXUM).

Paralectotype: 1 [sex unknown] ‘Syn- / type’, ‘ 185 in / Coll. / Bigot.’, ‘Coll. Bigot. / abt. 1845–93. / Pres. 1913 by / J.E. Collin.’ (OXUM). Note: The paralectotype is in poor condition: left prothoracic leg missing terminal four tarsomeres; abdomen and posterior part of thorax, including metathoracic legs, entirely missing (apparently consumed by dermestids); wings intact, but tip of left wing slightly damaged. The remaining parts suggest that the specimen was similar to the lectotype.

Notes: Macquart indicated that his description was based on a female. Of the two types, one is a male and the other lacks an abdomen. These carry modern syntype labels, and as it is reasonable to believe that Macquart saw both specimens, probably believing them to be female (many mistakes have been made in determining sex of these flies – even when using modern optics). For taxonomic stability I here designate the intact male as lectotype and the other specimen as paralectotype. Although the specimens do not carry locality data, Macquart records the following for his material ‘Du Cap. Collection de M. Serville’ and a large drawer label accompanies the material which reads ‘185 A. Dorsale . / C. B. Speil. [Cap Bone Spei = Cape of Good Hope] / (Coll. Serville) Macq. D. Eu.’. Although Oldroyd (1974) states ‘Type in Paris’, and so probably never consulted the types, he was able to correctly identify some specimens as dorsale , probably using the rather unreliable pattern of white abdominal setae as a key character.

Type locality: It is not known exactly where the types were collected. I designate Olifants River [31°27'S: 18°32'E] between Citrusdal and Clanwilliam as type locality as a good series has been collected there and the locality is central to the known range .

Other material examined: SOUTH AFRICA: 1♂ Aninaus Pass , 15 km W Steinkopf, 2917BA, 4.ix.1983, Londt & Stuckenberg, rocky hillside & dry river ( NMSA) ; 2♂ 2♀ 10 km E Port Nolloth , 29°17'S: 16°58'E, 26.viii.1995, Londt, 120 m, white sand Succulents ( NMSA) ; 2♀ 11 km N Komaggas , 29°43'S: 17°31'E, 24.viii.1995, Londt, 360 m, rocky slope flowers ( NMSA) ; 1♂ 2♀ 12 km W Soutfontein ,3017DA, 4.ix.1981, Londt, Schoeman & Stuckenberg, Succulent Karoo ( NMSA) ; 3♂ 10 km E Garies , 3017DB, 3.ix.1981, Londt, Schoeman & Stuckenberg, Succulent Karoo ( NMSA) ; 1♀ Studers Pass 22 km NE Garies, 3018AC, 6.ix.1983, Londt & Stuckenberg, stream edge & rocky slopes ( NMSA) ; 1♀ Wolfhok , 3018AC, 24 x.1986, Schoeman ( NMSA) ; 1♀ Bowesdorp [30°09'S: 17°56'E], xi.1931, Museum Staff ( SAMC) ; 1♀ Kamieskroon [30°12'S: 17°56'E], xi.1936, Museum Staff ( SAMC) ; 1♂ 1♀ Btw Kamieskroon [30°12'S: 17°56'E] & Springbok, x.1939, Mus. Staff ( SAMC) ; 1♂ Kamieskroon , Bakleikraal, 30°13'S: 18°03'E, 9–10 x.1994, Gess ( AMGS) ; 3♂ Farm Arkoep , 6 km N Kamieskroon, 30°19'S: 17°56'E, 1–2 x.1990, Eardley ( SANC) ; 1♂ 2♀ Wallekraal [30°24'S: 17°31'E] Namaqualand, x.1950, Mus Expd ( SAMC) ; 1♀ Klip Vlei , Garies [30°33'S: 17°59'E], xi.1931, Mus. Staff ( SAMC) ; 3♀ 20 km N Bitterfontein , 30°53'S: 18°11'E, 28.viii.1995, Londt, 180 m, roadside woody shrubs ( NMSA) ; 1♂ 17 mi [c. 27 km] N Vanrhynsdorp at fork Geelsbek & Sout rivers, 3118BC, 10 xi.1972, Irwin, 280 ft [c. 85 m] ( NMSA) ; 2♂ 7 mi [c. 11 km] N Vanrhysdorp , 3118BC, 10.ix. 1972, 400 ft [c. 120 m], red dunes ( NMSA) ; 1♂ 1♀ 10 km N Vanrhynsdorp , 3118DA, 2.ix.1981, Londt, Schoeman & Stuckenberg, Succulent Karoo ( NMSA) ; 1♂ 34.5 km S Soetwater , 3119CD, 29.ix –1 x.1977, Miller, 500 m, Malaise ( NMSA) ; 7♂ 12♀ Top Botterkloof Pass , 3119CD, 13.ix.1972, Irwin, 2230 ft [c. 680 m], white sand dune assoc. ( NMSA) ; 2♂ 2♀ Knersvlakte , North Van Rhynsdorp [31°15'S: 18°45'E], 6–9 x.1964, Stuckenberg ( NMSA) ; 1♂ 4♀ Knersvlakte [31°15'S: 18°45'E], x.1948, Mus. Staff ( SAMC) ; 1♂ Nieuwoudtville , Skuinshoogte Pass, 31°16'S: 19°08'E, 23–30.ix.1994, Gess, dry river bed ( AMGS) ; 1♂ 1♀ Akkerendam Nat. Res. , 31°21'02"S: 19°46'22"E, 5 xi.2002, Londt, 1020 m, Karoo bushes, reddish sand in valley ( NMSA) ; 2♂ 3♀ Akkerendam Nat. Res. , 31°26'54"S: 19°46'27"E, 5–6 xi.2002, Londt, 1050 m, Karoo bushes, W slope of small hill ( NMSA) ; 4♀ Akkerendam Nature Res. , 1 km N Calvinia, 31°26'56"S: 19°46'27"E, 10.x.2005, Londt, 1041 m, stony slope short vegetation ( NMSA) ; 1♀ Akkerendam Nat. Res. 1 km N Calvinia, 31°26'55"S: 19°46'22"E, 9–10 xi.1998, Londt, 1260 m, Karoo vegetation ( NMSA) ; 6♂ 11♀ Olifants River [31°27'S: 18°32'E] between Citrusdal & Clanwilliam, x–xi.1931, Museum Staff ( SAMC) ; 6♂ 11♀ Papendorp , Olifants River [31°27'S: 18°32'E], x.1950, Mus Expd ( SAMC) ; 3♂ 4♀ Kareedam Nat. Reserve , 1 km N Calvinia, 31°27'S: 19°47'E, 4–5. xi.1991, Londt, 1000 m ( NMSA) ; 1♂ 1♀ 12 km S Calvinia , 31°34'10"S: 19°43'56"E, 7.xi.2002, Londt, 1080 m, sandy roadside ( NMSA) ; 7♂ 8♀ 8 km E Lutzville , 31°36'S: 18°24'E, 29.viii.1995, Londt, 60 m, sandy slope flowers ( NMSA) ; 1♂ 2♀ 10 km North Vanrhynsdorp on N7 [31°37'S: 18°44'E], 15.ix.1992, Manning ( NMSA) ; 1♀ Doringbaai [31°49'S: 18°14'E], xi.1956, SAM ( SAMC) ; 1♂ 1♀ 5 km S Doringbaai , 31°51'S: 18°16'E, 29.viii.1995, Londt, 90 m, red ground flowers ( NMSA) ; 1♂ 1♀ 0.7km S Skurfkop Stn [31°57'S: 18°36'E], 25 x.1978, Whitehead ( SAMC) ; 3♂ 2♀ 5 km E Lambert’s Bay , 3218AB, 31.viii.1981, Londt, Schoeman & Stuckenberg, westcoast strandveld ( NMSA) ; 4♂ 1♀ 2.5 mi [c. 4 km] S Elandsbaai, 3218AD, 16.ix1972, Irwin, 30 ft [c. 9 m], coastal sand dunes ( NMSA) ; 3♂ 2♀ 4.5 mi [c. 7 km] S Elandsbaai, 3218AD, 17.ix.1972, Irwin, 50 ft [c. 15 m], coastal sand plain ( NMSA) ; 2♂ 1♀ 13 mi [c. 21 km] W Clanwilliam , 3218BA, 15.ix.1972, Irwin, 1625 ft [c. 450 m], hillside with flowers ( NMSA) ; 1♂ 32 km NE Clanwilliam, Brandewyn R., 3219AA, 2–3 x.1977, Miller ( NMSA) ; 1♀ Bulhoek [32°01'S: 18°47'E], Klaver – Clanw [between Klawer & Clanwilliam], x.1950, Mus. Exp. ( SAMC) ; 1♂ 2♀ Biedou Valley , 32°06'00"S: 19°19'00"E, 6.ix.1989, Londt, Stuckenberg & Croeser, 300 m, rocky gentle N slope scrub & wild flowers ( NMSA) ; 3♂ 3♀ Biedouw Valley , 32°06'S: 19°14'E, 1–12. ii.1991, Picker, 350 m, Succulent Karoo ( NMSA) ; 1♂ 1♀ Graafwater [32°09'S: 18°36'E], x.1947, Mus. Exp ( SAMC) ; 2♂ 11 km W Clanwilliam on road to Graafwater , 2–8 x.1990, Gess ( AMGS) ; 2♂ 5 km W Clanwilliam, road to Graafwater , 12 x.1987, Gess ( AMGS) ; 4♂ 4♀ 1?, Het Kruis [32°09'S: 19°02'E], x.1947, Mus. Exp. ( SAMC) ; 3♂ 1♀ East of Pakhuis Pass [32°09'S: 19°02'E], ix.1947, Mus. Exp. ( SAMC) ; 1♂ ‘ Clan William [Clanwilliam, 32°11'S: 18°54'E], ix.1928, Brauns ( NMSA) ; 1♂ 4 m S Clanwilliam [32°11'S: 18°54'E], ix.1961, SAM ( SAMC) ; 4♂ 3♀ Leipoldtville [32°13'S: 18°29'E], Eland’s Bay, x.1947, Mus. Exp. ( SAMC) ; 1♂ 2♀ Elands bay , Baboon Point [32°19'S: 18°19'E], 26.ix.1978, Whitehead ( SAMC) ; 1♀ Clanwilliam District , Klein Alexandershoek, 32°20'20"S: 18°46'E, 6 x.1988, Gess ( AMGS) ; 1♂ Ouberg Pass [32°24'S: 20°20'E] (SE Touws R.), xii.1962, SAM ( SAMC) ; 1♂ Paleisheuvel [32°28'S: 18°43'E], xi.1948, Mus Exp ( SAMC) ; 1♂ Cedarberg , 32°30'S: 19°15'E, 15 xi.1984, Prinsloo ( SANC) ; 2♂ 3♀ Tankwa Karoo [c. 32°30'S: 19°45'E], Waterval [32°35'S: 20°18'E], xi.1952, Mus Expd ( SAMC) ; 7♂ 11♀ 14 km NNW Citrusdal , 32°31'S: 18°58'E, 1 xi.1991, Londt, 300 m, woody plants sandy ( NMSA) ; 1♀ Nieuveld Escarpment , Rietvlei [32°33'S: 21°16'E], i.1949, Zinn – Hesse ( SAMC) ; 1♂ 8 m N Citrusdal [32°35'S: 19°01'E], ix.1961, SAM ( SAMC) ; 1♂ Citrusdal , 2 xi.1966, Rozen ( AMNH) ; 3♂ 3♀ Koornplanskloof , 10 km S Citrusdal, 32°40'S: 19°01'E, 4–8 x.1994, Danielsson, 200–270 m ( MZLU) ; 2♂ 3♀ Kagga Kamma Nat. Res. Swartruggens Mtn, 32°44'39"S: 19°33'12"E, 13.x.2005, Londt, 1027 m, sandy rocky tall fynbos ( NMSA) ; 5♂ 5♀ Kagga Kamma Nat. Res. Swartruggens Mtn, 32°45'16"S: 19°34'18"E, 10–12 x.2005, Londt, 1082 m, rocky sandy fynbos area ( NMSA) ; 3♂ 3♀ Knolfontein Farm c. 10 km S Kagga Kamma Nat. Res., 32°49'47"S: 19°37'32"E, 13 x.2005, Londt, 1264 m, sandy stony fynbos area ( NMSA) ; 1♀ Gonnemanskraal N Jacobsbaai, 32°57'14"S: 17°53'07"E, 9–10 xi.2002, Londt, 0–10 m, dune vegetation and rocks ( NMSA) ; 1♀ Saldanah , 3317BB, 8–9 x.1977, Miller ( NMSA) ; 1♂ 1♀ 14 mi [c. 22 km] SE Langebaan, 3318AA, 18.ix.1972, Irwin, 2000 ft [c. 610 m], coastal dunes and sandy plain ( NMSA) ; 1♂ 3♀ Saldanha Bay [33°03'S: 18°00'E], ix.1960, SAM ( SAMC) ; 16♂ 17♀ Hopefield [33°04'S: 18°21'E], ix.1960, SAM ( SAMC) ; 1♂ Konstable [Constable], 33°15'S: 20°18'E, xii.1962, SA Museum Expedition ( SAMC) ; 1♀ Ysterfontein [Yserfontein, 33°20'S: 18°09'E], 20 x.1964, Stuckenberg ( NMSA) ; 2♂ 5♀ Malmesbury [33°27'S: 18°44'E], 5 xii.1926, Brauns (1♂ 3♀ NMSA, 1♂ 2♀ BMNH) ; 1♀ Melkboschstrand [33°43'S: 18°26'E], 13 x.1948, Munro ( SANC) ; 1♀ Milnerton [33°52'S: 18°29'E], 3.xi.1931, Munro ( NMSA) ; 1♂ 4♀ Blackheath [33°57'S: 18°42'E], 9.x.1964, Gess ( SAMC) ; 6♂ 6♀ Strandfontein , 3418BA, 10–12.x.1977, Miller, Groot-Sandleegte ( NMSA) .

Distribution, phenology (Table 3) and biology: The species is found mainly in the western parts of South Africa ( Fig. 66 ) with records coming from the Western Cape and Northern Cape provinces. Adults are active during spring and summer (August– February) although most collections were made in October and November.

Similar species: Although the male genitalia are similar to those of eremia , leukoros , probolos and platygaster , in that the hypandria are elongate, males can be relatively easily separated using the key provided. Females are more difficult to identify, but the pale yellowish basal segments of the antennae usually associated with dorsalis is a fairly reliable character.

Figures

Figs 35–43. Acnephalomyia male terminalia: (35–37) A. dorsalis (Macquart, 1838) Knersvlakte, North of Vanrhynsdorp, lateral, dorsal and ventral; (38–40) A. eremia sp. n. holotype, lateral, dorsal and ventral; (41–43) A. iota sp. n. holotype, lateral, dorsal and ventral. Scale lines = 1 mm.

Fig. 66. Distribution of Acnephalomyia species: A. dorsalis (Macquart, 1838) – circles; A. eremia sp. n. – triangle.