Gonioscelis scapularis ( Macquart, 1838 )

Londt, Jason G. H., 2004, A review of the afrotropical genus Gonioscelis Schiner, 1866 (Diptera: Asilidae), with descriptions of new species, African Invertebrates 45, pp. 21-124 : 85-86

Gonioscelis scapularis ( Macquart, 1838)

Figs 107–109 , 147

Dasypogon scapularis Macquart, 1838: 44 [1839: 160].

Redescription: Based primarily on holotype ^ ( MNHN) .

Head: Antenna brown-yellow, setae dark red-brown and yellow. Facial swelling pronounced, mystax white in ventral two-thirds, dark red-brown in dorsal one-third, setae confined to gibbosity. Frons and vertex gold pruinose. Ocellar tubercle gold pruinose with many dark red-brown oc. Occiput gold pruinose, setae yellow. Proboscis and palpus dark red-brown, white setose.

Thorax (dirty and damaged): Dark red-brown, gold pruinose. Postpronotal lobes orange, contrasting with adjacent mesonotum, with long yellow-orange macrosetae and shorter yellow setae. Mesonotal setae: ac black; approx. 2–3 pairs dc, black, just extending anterior of transverse suture; approx. 5 yellow npl; 8–9 yellow and dark red-brown sa; approx. 5 yellow pa. Scutellum dark brown, with 4 yellow mrg sct. Wing length 8.7 mm, membrane yellow. Legs: Prothoracic mostly brown-yellow, spur region brownred, mesothoracic brown-yellow, femur with brown-red dorsal parts, metathoracic brown, femur with brown-yellow posterodorsal stripe, setae pale yellow-white. Prothoracic coxa black, gold-silver pruinose, white setose; femoral spur variable but acutely pointed (angle approx. 20–30°).

Abdomen: Tergites mostly dark red-brown (T6–8 orange-brown), gold pruinose, fine yellow setose. Sternites similar but last few yellowish.

Terminalia: ^ holotype not dissected. ơ terminalia ( Figs 107–109 ): Long ep, in dorsal view projecting further than proctiger, lobes not tapering greatly, each with a cluster of thick black setae positioned just before a downturned broadly rounded mostly asetose distal end; gcx distally with three distal projections, the most distal having a few fine setae associated with it; hyp, in ventral view, clearly longer than broad, upturned just beyond mid-length and tapering rapidly to a terminal almost club-shaped apex equipped with long fine setae.

Variation: Some individual variation is evident in the coloration of mesonotal macrosetae (lateral ones may be yellow or black) and legs (the extent of dark red-brown marks varies). Male genitalia are remarkably constant in form.

Type material: AFRICA: 1^ holotype (seen), Afrique, Delalande, 586 (MNHN).

Type locality: Here designated as South Africa: 4 km S. Clanwilliam .

Other material: SOUTH AFRICA: 3ơ 4^, ‘Near / Doornbosch [= Doringbos 2919CC]’ ~ ‘S.A.M. / 9:1961’ ( SAMC) ; 1ơ 4^, ‘ Giftsberg [= Gifberg 31°47'S 18°46'E], / Rhynsdorp. / C.C. Sept. 1911 ’ ( SAMC) ; 1ơ 3^, ‘ Clanwilliam / Nardouw [Mountains 31°55'S 18°45'E] / S.A. Museum’ ~ ‘ Mus. Staff / Sept. 1941 ’ ( SAMC) ; 3ơ 1^, ‘ Sth Africa Cape Prov / 30km S Clanwilliam / 3218BD 31.viii.1981 / J. Londt, L. Schoeman and B. Stuckenberg. / Karroid broken veld’; 2ơ 4^, ‘ Sth Africa : Cape Prov / 4km SW Clanwilliam / 32°11'30"S: 18°52'20"E / 28.viii.1989 225m / J Londt, B Stuckenberg / & P Croeser Sandy E slope macchia nr dam’; 1ơ 1?, ‘ South Africa / Clanwilliam [32°11'S 18°54'E] / Sept. 1947 / S. Walters’; 17ơ 37^, ‘ 4 m. S. of / Clanwilliam [32°11'S 18°54'E] / C.P.’ ~ ‘ S.A.M. / 9:1961’ ( SAMC) . 1ơ, ‘ S Afr C.P. / 25 km S / Clanwilliam / VB Whitehead / 30 Sept. 1981 ’ ( SAMC) ; 1ơ, ‘ Paleisheuwel [32°18'S 18°43'E] / C.P.’ ~ ‘ Mus., Exp., / Nov. 1948.’ ( SAMC) ; 7ơ 16^, ‘ Het Kruis [32°36'S 18°45'E] / C.P.’ ~ ‘ Mus. Exp. / Oct. 1947 ’ ( SAMC) ; 2ơ, ‘ Sth Africa: Cape Prov / Biedou Valley 300m / 32°06'00"S: 19°19'00"E / J Londt, B Stuckenberg / & P Croeser 6.ix.1989 / Rocky gentle N slope / Scrub & wild flowers’; 3ơ 4^, ‘ S. Africa: SW Cap #102 / Biedouw Valley / 32°06'S 19°14'E 350m / 1-12.ii.1991, M. Picker / Succulent Karoo’; 1^, ‘ Biedouw Valley / Namaqualand / 24/9/89 / M Picker / B Leon’; 1ơ 1^, ‘Pakhuis Pass [32°09'S 19°02'E] 950m / Clanwilliam Dist. / 17-19 Oct 1964 / B & P Stuckenberg’; 3ơ 1^, ‘ Pakhuis Pass / C.P.’ ~ ‘ S.A.M. / 9: 1961’ ( SAMC) ; 2ơ 5^, ‘ 8 m. N. of / Citrusdal [32°35'S 19°01'E]’ ~ ‘ S.A.M. / 9: 1961’ ( SAMC) .

Notes: Londt (1985: 48) transferred scapularis to Gonioscelis . Macquart states that the type was from ‘Du Cap’, but the label does not record this information. Macquart also indicated that the type was a male, but examination shows it to be a female. Material of a species identified by Hesse as setosus agrees very closely with the holotype and so it is now possible to describe the male of this species.

Distribution, phenology and biology (Tables 1–2, Fig. 147 ): The species appears to be confined to a fairly small area centred on the town of Clanwilliam, where it occurs sympatrically with pickeri whose females are indistinguishable from scapularis females (see pickeri for comment). All specimens were found in the Succulent Karoo biome and collected between August and November, although one sample bears the month of February which may indicate a longer adult phase (or a mislabeled November collection?). Specimens have been found on the ground in dry scrub areas. There is one Natal Museum prey record as follows: 1^ (Biedouw Valley) – Coleoptera (Buprestidae) . Similar species: A species closely related to ceresae , haemorhous , hispidus and pickeri in that males possess a single distomedial hypandrial projection. The hypandrium, however, is much longer and upwardly curved. The epandrial lobes are characteristically downturned distally in lateral view. It is possible that all these species are geographical variants of one species, but more information is required before this can be ascertained. G. melas also has a single distomedial hypandrial process, but is otherwise rather different and perhaps is more closely related to punctipennis and its allies (see comment under melas ).

Figures

Figs 101–112. Gonioscelis male genitalia. 101–103. G. punctipennis Engel, 1925 (25 km N Kamieskroon). 101. Lateral. 102. Dorsal. 103. Ventral. 104–106. G. ramphis sp. n. (Mahalapye paratype). 104. Lateral. 105. Dorsal. 106. Ventral. 107–109. G. scapularis (Macquart, 1838) (4 km SW Clanwilliam). 107. Lateral. 108. Dorsal. 109. Ventral. 110–112. G. submaculatus Speiser, 1910 (Zomba). 110. Lateral. 111. Dorsal. 112. Ventral. Scale lines = 1 mm.

Figs 146–147. Distribution of Gonioscelis species found only in southern Africa. 146. closed circle = bykanistes, open circle = cuthbertsoni, closed square = hadrocantha, open square = mantis. 147. closed circle = engeli, open circle = scapularis, closed square = ventralis, open square = xanthochaites.