Gonioscelis ramphis, Londt, 2004

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 : 83-84

Gonioscelis ramphis sp. n.

Figs 104–106 , 149

Gonioscelis ventralis: Engel 1925: 167 ( Fig. 2 ơ genitalia) (misidentification).

Etymology: Gr. ramphis – hook. Refers to the strongly down-turned or hooked epandrial lobes.

Description: Based primarily on holotype ơ (NMSA).

Head: Antenna dark red-brown to black, a little orange at junction between pedicel and postpedicel, short yellow setose. Facial swelling poorly developed, mystax uniform yellow-white, somewhat weaker between antennal sockets and gibbosity. Frons and vertex thinly gold pruinose. Ocellar tubercle weakly pruinose with yellow oc. Occiput silver-gold pruinose, setae yellow-white. Proboscis and palpus dark red-brown, pale yellow setose.

Thorax: Dark red-brown to black, silver-gold pruinose. Postpronotal lobes (and small part of adjacent mesonotum) orange, contrasting with mesonotum, with small yellow setae. Mesonotal setae yellow-white: ac not evident; dc 5 pairs, not extending anterior of transverse suture; 3 npl; 3–4 sa; 3 pa. Scutellum dark red-brown to black, with 4 yellow-white mrg sct. Wing length 8.5 mm, membrane mostly yellow. Legs: Mostly orange, dark red-brown areas as follows – proximal part of anterior face of prothoracic femur, narrow ventral strip on meso- and metathoracic femora, macrosetae black, a few white on pro- and mesothoracic tibiae. Prothoracic coxa dark red-brown to black, silvergold pruinose, yellow-white setose; femoral spur moderately pointed (angle approx. 50°).

Abdomen: Tergites dark red-brown to black, silver pruinose, setae short yellow except on T1 where they are longer. Sternites similar to tergites but apruinose, with setae tiny yellow.

Terminalia ( Figs 104–106 ): Proctiger slightly shorter than ep, ep lobes with strongly downturned and tapering tips equipped with fine setae; gcx distally with two dorsodistal projections and a group of short macrosetae; hyp, in ventral view, slightly broader than long, tapering moderately quickly to about mid-length and terminating in a bilobed apex equipped with short fine setae. The illustration provided by Engel (1925, Fig. 2 ) clearly represents ramphis and was probably drawn from the Waterberg material he studied.

Variation:A reasonably constant species demonstrating only slight individual variation and sexual dimorphism. Some size variation is noted in the Leon Taljaard material (i.e. wing length: shortest – 9.1 mm, longest – 11.8 mm).

Type material: BOTSWANA: 1ơ 1^ paratypes, ‘Mahalapye [23°04'S 26°50'E] / Bechuanaland / T. Schofield / iv.1960 ’. SOUTH AFRICA: 1ơ paratype, ‘South Africa. Transvaal / Kruger Park 5-I-1974 2431Db / 20km NNE of Tshokwane / near road junction S35-S37 / B&P Stuckenberg open savanna’; 1ơ holotype, 1ơ 4^ paratypes, Sth Africa: Transvaal / Kruger National Park / Vicinity of Skukuza / 9-12.iv.1985 J. Londt / SE2431DC Bushveld’; 1^ paratype, ‘S Africa: NW Province / Botsalano Game Reserve / Mogalodi Hide area / 25°33'15"S: 25°40'16"E / 1350m 18.iii.2003 J Londt / Rhus, Acacia savanna’; 2ơ 2^ paratypes, ‘Platriver [Plat River 25°10'S 28°05'E] / Wtb. [Waterberg] Distr. / 1-11 [? ii or xi] 1903 / R. v. Jutrencha’, ‘Ex Coll / Transv. Mus’, ‘Sammlung / F. Hermann’, ‘Afr. Orient. / Gonioscelis / ventralis / ơ Schin.’ (ZSMC); 2^ 1? paratypes, ‘Waterberg / Dist. 1898-99 / v. Jutrzencka’, ‘Ex Coll / Transv. Mus’, ‘ xanthopus’, ‘ G. / ventralis / det. Engel’, ‘ Gonioscelis / ventralis Schin. / det. E.O. Engel ^’ (ZSMC); 1ơ 2^ paratypes, ‘S Africa: NW Province / Leon Taljaard Nature Reserve / 26°55'32"S: 24°41'55"E / 1230m 13.iii.2003 J Londt / Acacia Erogrostis savanna’.

Other material: ZIMBABWE: 1^, ‘29 Nov 09 / Bulawayo [20°09'S 28°35'E] / 2 illegible words ’ (ID G. longulus by Bromley 1945) ( NMNH) .

Type locality: South Africa: Kruger National Park , Vicinity of Skukuza .

Notes: Engel (1925), under G. ventralis , listed ‘5^^, 2ơơ Waterberg’ as being in ZSMC. I have seen 2ơ 2^ 1? from the Waterberg (listed above) that I believe to be some of these specimens. Engel’s Fig. 2 was with little doubt drawn from one of these males and accurately portrays the genital form. The single Zimbabwean female misidentified by Bromley as longulus is listed above, but as the specimen is in poor condition confirmation of this range is required.

Distribution, phenology and biology (Tables 1–2, Fig. 149 ):A relatively poorly collected species found in the north-eastern parts of South Africa and possibly in south-west Zimbabwe. Confirmed records fall within a triangle over eastern Botswana, the North West and Mpumalanga Provinces of South Africa. All records occur within the vast Savanna biome, so a much wider distribution may be anticipated. Collections have been made between January and April (no records for February). The species rests on low vegetation in savanna mostly dominated by Acacia species. There is one Natal Museum prey record as follows: 1^ (Kruger National Park) – Lepidoptera (Ctenuchidae) .

Similar species:A member of the large and widely distributed group of species possessing a poorly defined facial gibbosity. This fairly distinctive species is perhaps most similar to ventralis and hadrocantha with respect to genital form (bilobed hypandrium and distally down-turned epandrial lobes).The hypandrium is long and shows some similarity to species occurring further north (e. g. batyleon and congoensis ) while the down-turned part of the epandrial lobes is far more pointed than seen in ventralis and hadrocantha .

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 148–149. Distribution of Gonioscelis species found only in southernAfrica. 148. closed circle = genitalis, open circle = longulus, closed square = maculiventris, open square = phacopterus. 149. closed circle = lacertosus, open circle = nigripennis, closed square = ramphis, open square = truncatus.

Figs 2–5. Gonioscelis species, head, showing development of facial gibbosity and mystax. 2. G. submaculatus Speiser, 1910 (Valley of Lower Shire), poorly defined gibbosity, and mystax extending fairly strongly to antennal sockets. 3. G. longulus Ricardo, 1925 (Paul Roux), moderate gibbosity, and mystax extending moderately to antennal sockets. 4. G. lacertosus Engel, 1925 (Hantamsberg Summit), moderate gibbosity, and small weak setae between gibbosity and antennal sockets. 5. G. punctipennis Engel, 1925 (Garies), well-developed gibbosity, and complete lack of setae between gibbosity and antennal sockets.