Gonioscelis ceresae Oldroyd, 1974

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 : 36-37

Gonioscelis ceresae Oldroyd, 1974

Figs 27–29 , 150 Gonioscelis ceresae Oldroyd, 1974: 39 ( Fig. 27 foreleg). Redescription: Based primarily on holotype ơ (BMNH). Head: Antenna dark red-brown, setae mostly dark red-brown (a few brown-yellow dorsally). Facial swelling pronounced, mystax uniform shiny yellow. Frons and vertex red-gold pruinose. Ocellar tubercle apruinose with dark red-brown oc. Occiput silver pruinose except for extensive shiny areas dorsally behind vertex, setae yellowish. Proboscis and palpus dark red-brown with yellow setae.

Thorax: Dark red-brown, gold pruinose. Postpronotal lobes brown-orange, clearly contrasting with adjacent mesonotum, with many long yellow setae. Mesonotal setae yellow: ac not evident; approx. 5 pairs dc, a few small setae extending anterior of transverse suture; 3 weak npl; 3 weak sa; approx. 5 weak pa. Scutellum dark red-brown with orange margin and approx. 6 weak yellow mrg sct. Wing length 8 mm, membrane mostly brownish. Legs mostly orange except for anterior face of prothoracic femur which is partly brown-red. Prothoracic coxa black, gold pruinose, yellow setose; femoral spur sharply pointed (angle approx. 25°).

Abdomen: Tergites mostly dark red-brown, mostly silver-gold pruinose (central parts apruinose), setae yellow, long. Sternites mostly orange-brown, entirely apruinose, setae few, yellow, long.

Terminalia ( Figs 27–29 ): Moderately short ep (proctiger projecting slightly beyond epandrial lobes), broad distally in lateral aspect (not obviously tapering distally), with minor setae in distal part; gcx with two projections and a group of long, welldeveloped setae distally; hyp, in ventral view, with maximum breadth slightly greater than maximum length, tapering quickly to well-defined, slightly clubshaped, short medial lobe.

Variation: A fairly uniform species showing little sexual dimorphism (setae of female generally shorter).

Type material (all seen): SOUTH AFRICA: 1ơ holotype, South Africa, Cape Prov, Ceres [33°22'S 19°19'E], xii.1924, R.E. Turner, BM 1925-44 ( BMNH) ; 5^ paratypes, same data as holotype ( BMNH) ; 6ơ 7^ paratypes, Ceres , xi.1920, R.E. Turner, BM 1920-497 ( BMNH) ; 1ơ 1^ paratypes, Ceres , 1500', xii.1920, R.E. Turner, BM 1921- 38 ( BMNH) ; 1ơ 3^ paratypes, Ceres , 1–12.xi.1920, R.E. Turner, BM 1924-503 ( BMNH) .

Other material: SOUTH AFRICA: 1ơ, ‘Witzenberg Vall. [Pass 33°16'S 19°13'E] / 3,500 ft. / Ceres District, / Cape Province. / 21-23.xii.1920.’, ‘ S. Africa. / R.E. Turner. / Brit. Mus. / 1921-38’ ( BMNH); 7ơ 9^, ‘ Upper Sources / Olifants River / Ceres [33°22'S 19°19'E] C.P.’ ~ ‘ Mus. Exp. / Dec. 1949 ’ ( SAMC) .

Type locality: South Africa: Western Cape, Ceres .

Distribution, phenology and biology (Tables 1–2, Fig. 150 ): Known only from the Ceres district of the Western Cape province of South Africa. This is an area within the Fynbos biome. The species has been collected in November and December.

Similar species: A species closely similar to haemorhous , hispidus , pickeri and scapularis in that males possess a single distomedial hypandrial projection. The hypandrium, however, is much shorter and stouter than that of the other species. It is possible that all these species are no more than geographical variants of one species, but more information is required before this can be ascertained. G. melas also has males with a single distomedial hypandrial process, but is otherwise different and is probably more closely related to punctipennis and its allies (see comment under melas ).

Figures

Figs 18–29. Gonioscelis male genitalia. 18–20. G. amnoni sp. n. (holotype). 18. Lateral. 19. Dorsal. 20. Ventral. 21–23. G. batyleon sp. n. (holotype). 21. Lateral. 22. Dorsal. 23. Ventral. 24–26. G. bykanistes sp. n. (Hotazel paratype). 24. Lateral. 25. Dorsal. 26. Ventral. 27–29. G. ceresae Oldroyd, 1974 (holotype). 27. Lateral. 28. Dorsal. 29. Ventral. Scale lines = 1 mm.

Figs 150–151. Distribution of Gonioscelis species found only along the west coast of South Africa. 150. closed square = ceresae, cross = iota, open circle = melas. 151. closed circle = chloris, open circle = exouros, closed square = kedros, open square = punctipennis.