Sceliotrachelus braunsi Brues, 1908

van Noort, Simon, Lahey, Zachary, Talamas, Elijah J., Austin, Andrew D., Masner, Lubomir, Polaszek, Andrew & Johnson, Norman F., 2021, Review of Afrotropical sceliotracheline parasitoid wasps (Hymenoptera, Platygastridae), Journal of Hymenoptera Research 87, pp. 115-222 : 115

Sceliotrachelus braunsi Brues

Figs 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 49

Sceliotrachelus braunsi Brues, 1908: 13 (original description); Kieffer 1926: 606 (description); Masner 1964: 9 (description); Masner 1965: 302 (type information); Kozlov 1972: 134 (keyed); Masner and Huggert 1989: 113, 115, 154, 182, 197 (catalogued, illustrated); Vlug 1995: 75 (catalogued, type information).

Material examined.

Holotype: South Africa • ♂; Eastern Cape, Algoa Bay, Cape Colony ; 10 November 1896; H. Brauns; Sceliotrachelus braunsi Brues (MCZ). Photographs of holotype examined (Fig. 29 ).

Paratype: South Africa • ♂; same data as holotype (MCZ) .

Additional material examined.

South Africa • ♀ ; Eastern Cape: 1♀ ; 1♂ Schilpad Laagte Farm, (14.7 km 229°SW Kirkwood); 33°31.104'S, 25°22.353'E; 9-16 Feb 2001; HG Robertson and R Tourle; Pitfall; VB01-A2T-P02; Valley Bushveld (goat trashed) [Sundays Thicket]; SAM-HYM-P030896 (SAMC) • 3♀♀; 1♂ Blauwe Krans Farm, (12.8 km 216°SW Kirkwood); 33°30.747'S, 25°24.644'E; 9-16 Feb 2001; HG Robertson and R Tourle; Pitfall; VB01-A3T-P03; Valley Bushveld (goat trashed) [Sundays Noorsveld]; SAM-HYM-P030894 (SAMC; OSUC) • 2♀♀; idem except for VB01-A3T-P06; SAM-HYM-P030897 (SAMC) • 1♀; Blauwe Krans Farm, (12.8 km 216°SW Kirkwood); 33°30.747'S, 25°24.644'E; 9-16 Feb 2001; HG Robertson and R Tourle; Pitfall; VB01-A3N-P06; Valley Bushveld (non-trashed) [Sundays Noorsveld]; SAM-HYM-P030898 (SAMC) • 1♀; Februarie Farm, (40.2 km 267°W Kirkwood); 33°33.124'S, 25°03.043'E; 10-17 Feb 2001; HG Robertson and R Tourle; Pitfall, VB01-R1T-P01; Valley Bushveld (goat trashed) [Sundays Thicket]; SAM-HYM-P030899 (SAMC) • 1♀; idem except for VB01-R1T-P08; SAM-HYM-P030900 (SAMC) • 1♀; Februarie Farm, (39.9 km 268°W Kirkwood); 33°32.813'S, 25°03.091'E; 10-17 Feb 2001; HG Robertson and R Tourle; Pitfall VB01-R2N-P04; Valley Bushveld (non-trashed) [Sundays Thicket]; SAM-HYM-P030895 (SAMC) • 1♂; idem except for VB01-R2N-P05; SAM-HYM-P030901 (SAMC) • 1♀; 30 km S. Steytlerville, Baviaanskloof Mtns., Wolwerkrall Farm ; 33°33.88'S, 24°20.95'E; 17.XI.1999; M.E. Irwin et al.; MT across dry creek; SA-08; [Gamtoos Thicket] (CNCI) .

Description.

Female body length: 2 mm; male body length: 2 mm. Colour of head and mesosoma black; metasoma light brown with lateral tergites below lateral keel orange-brown; scape, pedicel, flagellar segments in female, legs orange-brown; flagellar segments in male black; foamy structures white; wings with dark brown and white patches.

Head 1.15 × wider than long, strongly narrowing towards toruli and clypeus; eye height equal to inter-ocular distance; malar space 0.6 × eye length; antennal length ratios (female): scape 13, pedicel 3, funicle 5, clava 10; male antennae filiform: scape 13, pedicel 3, flagellum 30; LOL:OOL:POL (2.5:5.5:5.5); occipital carina present, without occipital pit with numerous long white setae. Mesoscutum. Sculpture of mesosoma smooth, polished; ronotum transverse, strongly delta-shaped with strong medial longitudinal sulcus anteriorly with numerous long white setae; shoulders pointed, strongly humped in lateral view; mesoscutum very short, 3 × wider than long; medial length approximately equivalent to pronotum and scutellum; admedian depressions short, deep grooves, extending posteriorly beyond anterior apex of notauli; notauli align with grooves on either side of the narrow mesoscutellar disc; axillar carinae expanded into thick ridge; axillae strongly and broadly excavated; posterior margin of scutellum strongly raised in lateral view; propodeum with foamy structures extending to T1; mesopleuron polished, dorsally with three incomplete transverse ridges; extremely longitudinally compressed, 5 × higher than long; mesopleural carina moderately strong; foamy structures present posteriorly on metapleuron, concealing metapleural carina, metapleuron ventrally with dense patch of white setae; fore wing narrow, 3 × longer than wide, brachypterous, reaching just beyond posterior margin of T2; submarginal vein of fore wing absent; wing microtrichia strong, needle-like; hind wing with a strong, thickened marginal vein.

Metasoma. T1 transverse in dorsal view with dense row of setae on posterior margin overlapping T2; T2 large, as long as wide, 0.7 × metasomal length, with anterior transverse furrow c. equivalent to length of T1, centrally situated, encompassing two-thirds of anterior tergite width; T2 anteriomedially polished grading into posterior micro-reticulate area, bounded anterolaterally by more strigate area.

Male as in female, except for antennal configuration: eight funicular segments, first as long as second and third combined; second to seventh subequal in length, 2 × longer than wide; ultimate segment longer than penultimate segment.

Diagnosis.

The shape and colour pattern of the fore wings immediately distinguish this species from the other two species, which either have a much more brachypterous or normal fore wing shape. The hind wing costal margin has a thick band of black sclerotization that runs nearly the entire length of the wing, which is absent in the other two species. Strong genal and pronotal rugae are present, absent in the other two species. The mesosoma is the most longitudinally compressed of the three species with the pronotum, mesoscutum and scutellum all extremely transverse and of equal length. Strong white setae are present on the occiput and pronotum. The mesoscutum is posteriorly strongly raised in lateral view; mesoscutum compressed, narrow 2.5 × wider than long, without raised carinae; pronotal shoulders taper to point; wings slightly shortened, extending just beyond posterior margin of second tergite, 3 × longer than wide.

Etymology.

Named by Brues after the collector of the two type specimens, Dr Hans Heinrich Justus Carl Ernst Brauns, a medical doctor who practiced in Willomore in the Eastern Cape. The Brauns collection of Apocrita Hymenoptera was purchased by the Transvaal Museum (now Ditsong Museums of South Africa) for £1500 ( Kock and Krüger 1972; Anonymous 2020; Biodiversity Explorer 2020). The Brauns collection includes over 10,600 species represented by about 70,000 specimens and approximately 900 types ( Ditsong Museums of South Africa 2018). However, a number of the types could not be found in the collections held at Ditsong, (Audrey Ndaba, Collections Manager, pers. comm. 2018) and their precise whereabouts is of concern.

Distribution and habitat association

(Fig. 50 ). This species is currently only known from the Eastern Cape Province where the species is associated with three vegetation types that are endemic to the province. The following vegetation distributional summaries were extracted verbatim from Mucina and Rutherford (2006):

Gamtoos Thicket (coastal basin of the Gamtoos River Valley, south of the Baviaanskloof Mountains and along some smaller river valleys such as that of the Kromme River; also found north of the Baviaanskloof Mountains in more xeric conditions on some low ridges south and southeast of Steytlerville; altitude 0-700 m).

Sundays Noorsveld (mostly north of the Klein Winterhoek Mountains, centred around Waterford and the Darlington Dam and a smaller area from Jansenville westwards; also some patches south of this mountain range west of Kirkwood in the Sundays River Valley; altitude 100-600 m).

Sundays Thicket (from the surrounds of Uitenhage and the northern edge of Port Elizabeth into the lower Sundays River Valley to east of Colchester and northwards to the base of the Zuurberg Mountains and stretching westwards north of the Groot Winterhoek Mountains to roughly the Kleinpoort longitude; also an extensive area north of the Klein Winterhoek Mountains including much of the Jansenville District and parts of the far-southern Pearston District and far-western Somerset East District; altitude 0-800 m).

The current distribution is likely to be an artefact of under-sampling and the species is expected to be more widespread in the Eastern Cape (Fig. 50 ).

Comments.

The female specimen (Fig. 35 ) in CNCI has most of the long setae that are normally present on the head and mesosoma missing. These have clearly been dislodged, probably as part of a cleaning process. The specimen is unusually clean for a Sceliotrachelus , specimens of which usually have some degree of a covering of exudate, presumably as a result of their association with the leaf litter habitat or host association. The basal remnants of the setal insertions are evident on close examination of the pronotum and occiput, and all other characters support the determination of this specimen as S. braunsi .

Figures

Figure 29. Sceliotrachelus braunsi holotype male (MCZ) (MCZ-ENT 00030989) A habitus, lateral view B habitus, dorsal view C head, anterior view D head, mesosoma, lateral view E hind wing, ventral view (inset: data labels) F fore wing, dorsal view. Photos are President and Fellows of Harvard College, Museum of Comparative Zoology, Harvard University.

Figure 30. Sceliotrachelus braunsi female (SAMC) A, C, E, F (SAM-HYM-P 030896) B, D (SAM-HYM-P 030897) A habitus, lateral view B habitus, dorsal view C propodeum, T 1 - 2, lateral view D propodeum, T 1 - 2, dorsal view E head, anterior view F antenna dorsolateral view.

Figure 31. Sceliotrachelus braunsi female (SAMC) A, E, F (SAM-HYM-P 030896) B-D (SAM-HYM-P 030894 a) A fore wings, dorsal view B fore wing, medial region detail C fore wing, dorsal view D fore wing, setae detail E hind wing ventral view F data labels.

Figure 32. Sceliotrachelus braunsi male (SAMC) (SAM-HYM-P 030894 b) A habitus, dorsal view B habitus, lateral view C head, mesosoma, dorsolateral view D head, mesosoma, dorsal view E head, mesosoma, dorsolateral view F head, anterolateral view.

Figure 33. Sceliotrachelus braunsi male (SAMC) (SAM-HYM-P 030894 b) A mesoscutum, propodeum, metasoma dorsoposterior view B head, antennae, anterolateral view C head, mesosoma, ventral view D head, mesosoma, ventrolateral view.

Figure 34. Sceliotrachelus braunsi female (SAMC) (SAM-HYM-P 030898) A habitus, lateral view B habitus, dorsal view C head, mesosoma, dorsolateral view D head, mesosoma, dorsoposterior view E habitus, ventral view F foreleg.

Figure 35. Sceliotrachelus braunsi female (CNCI) A habitus, lateral view (inset: data labels) B habitus, dorsal view C head, mesosoma, dorsal view D head, mesosoma, lateral view E head, anterior view F habitus, anteroventral view.

Figure 36. Sceliotrachelus braunsi female SEM photos (SAMC) (SAM-HYM-P 030894 c) A occiput, posterior view B occiput, pronotum, lateral view C mesosoma, dorsal view D mesosoma, posterodorsal view E propodeum, T 1, lateral view F T 1, dorso-lateral view G fore tibial spur and basal tarsal comb, axial view H hind tibial spurs.

Figure 49. Comparison of selected characters for the three Sceliotrachelus species A-C shape of inter-antennal process D-F post-occiput G-I genal sculpture J-L fore wing M-O hind wing. A, D, G, J, M S. braunsi B, E, H, K, N S. karooensis C, F, I, L, O S. midgleyi.

Figure 50. Distribution of Sceliotrachelus species. Blue circle: Sceliotrachelus braunsi; red circle: Sceliotrachelus karooensis; white circle: Sceliotrachelus midgleyi. Biome map generated from Rutherford et al. (2006).