Sceliotrachelus midgleyi van Noort, 2021

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 midgleyi van Noort sp. nov.

Figs 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49

Material examined.

Holotype: South Africa • ♀; Eastern Cape, Asante Sana Game Reserve, Zuurkloof ; 32°17.092S, 25°00.521E; 1204 m; 18-25 Nov 2009; J. Midgley; T2S1c; Pitfall trap; Camdeboo Escarpment Thicket; Acacia thicket; next to river bed with larger trees; SAM-HYM-P046650 (SAMC).

Paratypes: South Africa • 3♀♀, 1♂ ; Eastern Cape, Asante Sana Game Reserve, buttress between Waterkloof and Zuurkloof ; 32°16.932S, 24°58.795E; 1401 m; 18-25 Nov 2009; J. Midgley; T1S1e; Pitfall trap; Camdeboo Escarpment Thicket, Open habitat, low shrubs and mat forming wild carnation, scattered grass; SAM-HYM-P036025A-D (SAMC) • 1♀ idem except for SAM-HYM-P038230 (SAMC) • 4♀♀; idem except for SAM-HYM-P046654 (SAMC) • 1♂; Asante Sana Game Reserve, Zuurkloof ; 32°17.099S, 25°00.527E; 1207 m; 18-25 Nov 2009; J. Midgley; T2S1e; Pitfall trap; Camdeboo Escarpment Thicket; Acacia thicket; next to river bed with larger trees SAM-HYM-P036026; SAM-HYM-P046646; SAM-HYM-P046649 (SAMC) • 2♀♀; Asante Sana Game Reserve, Zuurkloof ; 32°16.461S, 25°00.067E; 1406 m; 18-25 Nov 2009; J. Midgley; T2S2c; Pitfall trap; Camdeboo Escarpment Thicket; Mixed thicket with some small shrubs and larger trees; sparse grass; SAM-HYM-P036028 (SAMC) • 2♀♀; 1♂; idem except for SAM-HYM-P046648 (SAMC) • 1♂; Asante Sana Game Reserve, buttress between Waterkloof and Zuurkloof ; S 32 17.003 E 24 58.298; 1202 m; 18-25 Nov 2009; J. Midgley; T1S5d; Pitfall trap; Camdeboo Escarpment Thicket; Acacia thicket; stony ground; SAM-HYM-P036030 (SAMC) • 1♂; Asante Sana Game Reserve, Waterkloof ; 32°15.692S, 24°57.095E; 1415 m; 18-25 Nov 2009; J. Midgley; T3S1d; Pitfall trap; Camdeboo Escarpment Thicket; Mixed grass (low mat forming and tall) and small trees SAM-HYM-P036031 (SAMC) • 1♀; Asante Sana Game Reserve, Zuurkloof ; 32°16.011S, 25°00.244E; 1621 m; 18-25 Nov 2009; J. Midgley; T2S3d; Pitfall trap; Camdeboo Escarpment Thicket; Tall grass stands with scattered oubos and scattered other shrubs; SAM-HYM-P036032 (SAMC) • 1♀; Asante Sana Game Reserve, buttress between Waterkloof and Zuurkloof ; 32°16.934S, 24°58.801E; 1400 m; 18-25 Nov 2009; J. Midgley; T1S1d; Pitfall trap; Camdeboo Escarpment Thicket; Open habitat; low shrubs and mat forming wild carnation; scattered grass; SAM-HYM-P036033 (SAMC) • 1♀; Asante Sana Game Reserve, Zuurkloof ; 32°16.463S, 25°00.062E; 1407 m; 18-25 Nov 2009; J. Midgley; T2S2d; Pitfall trap; Camdeboo Escarpment Thicket; Mixed thicket with some small shrubs and larger trees; sparse grass; SAM-HYM-P036034 (SAMC) • 2♀♀; Asante Sana Game Reserve; buttress between Waterkloof and Zuurkloof ; 32°16.363S, 24°58.989E; 1793 m; 18-25 Nov 2009; J. Midgley; T1S3e; Pitfall trap; Camdeboo Escarpment Thicket; Steep rocky slope; dense shrubs (50 cm high) little to no grass; SAM-HYM-P040038 (SAMC) • 1♂; Asante Sana Game Reserve, buttress between Waterkloof and Zuurkloof ; 32°16.580S, 24°58.942E; 1618 m; 18-25 Nov 2009; J. Midgley; T1S2a; Pitfall trap; Camdeboo Escarpment Thicket; Steep slope; mostly small shrubs; fynbos; with some grass tussocks; SAM-HYM-P046643 (SAMC) • 1♂; Asante Sana Game Reserve, Zuurkloof ; 32°16.462S, 25°00.054E; 1413 m; 18-25 Nov 2009; J. Midgley; T2S2e; Pitfall trap; Camdeboo Escarpment Thicket; Mixed thicket with some small shrubs and larger trees; sparse grass; SAM-HYM-P046644 (SAMC) • 2♂♂; idem except for SAM-HYM-P046645 (SAMC) • 1♀; 1♂; Asante Sana Game Reserve, Waterkloof ; 32°16.994S, 24°56.311E; 1205 m; 18-25 Nov 2009; J. Midgley; T3S6e; Pitfall trap; Camdeboo Escarpment Thicket; Acacia thicket; SAM-HYM-P046647; SAM-HYM-P046655 (SAMC) • 1♀; Asante Sana Game Reserve, buttress between Waterkloof and Zuurkloof ; 32°16.370S, 24°58.986E; 1805 m; 18-25 Nov 2009; J. Midgley; T1S3c; Pitfall trap; Camdeboo Escarpment Thicket; Steep rocky slope; dense shrubs (50 cm high) little to no grass; SAM-HYM-P046651 (SAMC) • 1♀; Asante Sana Game Reserve, Zuurkloof ; 32°16.462S, 25°00.084E; 1412 m; 18-25 Nov 2009; J. Midgley; T2S2a; Pitfall trap; Camdeboo Escarpment Thicket; Mixed thicket with some small shrubs and larger trees; sparse grass; SAM-HYM-P046652 (SAMC) • 1♀; Asante Sana Game Reserve, Waterkloof ; 32°16.993S, 24°56.325E; 1197 m; 18-25 Nov 2009; J. Midgley; T3S6c; Pitfall trap; Camdeboo Escarpment Thicket; Acacia thicket; SAM-HYM-P046653 (SAMC) .

Description.

Female body length: 2.26 mm; male body length: 2 mm. Colour of head and mesosoma black; metasoma dark brown to black, with lighter brown areas anteriolaterally; scape, pedicel, flagellar segments in female, legs orange-brown; flagellar segments in male dark brown; foamy structures pale yellow; wings yellow-white with broad darker band in apical half.

Head 1.27 × wider than long, strongly narrowing towards toruli and clypeus; eye height 0.9 × inter-ocular distance; malar space 0.55 × eye length; antennal length ratios (female): scape 14, pedicel 2.5, funicle 5.5, clava 10; male antennae filiform: scape 15, pedicel 4, flagellum 35; LOL:OOL:POL (4:7:7); hyperoccipital carina present, collared, without occipital pit, long setae present.

Mesoscutum. Sculpture of mesosoma polished; pronotum transverse, strongly delta-shaped with medial longitudinal sulcus, with anteriorly projecting neck, covered in scattered long brown setae; shoulders angular, flat in lateral view; mesoscutum short 2.3 × wider than long medially; 1.3 × medial length of pronotum and equivalent to scutellar length; admedian depressions short, deep grooves, not overlapping longitudinally with posterior narrow and more shallow notauli, which are widely spaced; median mesoscutal line present; notaular excavations align with two deep and long parallel excavations of the axillular carina, which meet with the scutoscutellar sulcus, itself not widened; mesoscutellar disc medially and longitudinally evenly raised into hump; axillar carinae present and strongly raised; axillae weakly and evenly excavated; posterior margin of mesoscutellum not raised in lateral view; propodeum with foamy structures extending to T1; mesopleuron polished, dorsally with two complete transverse ridges; not longitudinally compressed, 1.9 × higher than long; mesopleural carina strong, curled dorsally; foamy structures present posteriorly on metapleuron, concealing metapleural carina, metapleuron ventrally with dense patch of white setae; fore wing brachypterous, not extending beyond posterior margin of T2, narrow> 4 × longer than wide, curved forwards in boomerang-shape; submarginal vein of fore wing absent except at base, narrow and almost glabrous with scattered microtrichiae for basal third, dense microtrichiae present over distal two-thirds; hind wing with marginal vein absent, except for basal remnant, anterior margin angled at hamulus, narrow and almost glabrous with scattered microtrichiae for basal half, dense microtrichiae present over distal half.

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 0.5 × length of T1, centrally situated, encompassing central three-quarters of anterior tergite width; T2 anteromedially polished grading into lateral strigulate areas, and posteriorly aerolate-rugulose.

Male as in female, except for antennal configuration: eight funicular segments, first 1.3 × as long as second and third combined; second to seventh subequal in length, 2 × longer than wide; ultimate segment longer than penultimate segment.

Diagnosis.

This species is immediately distinguishable by the brachypterous wings, which have a unique colour pattern, are extremely narrow, 4 × longer than wide, and do not extend beyond the posterior margin of tergite 2. It shares the lack of the occipital pit, presence of long setae on the pronotum, and presence of strong microtrichiae with S. braunsi , but does not have rugae present on the genae and pronotum as in S. braunsi ; has a wider mesoscutum (twice as wide as long, as opposed to 2.5 × in S. braunsi ); a distinctive mesoscutellar disc which is square in shape and medially and longitudinally evenly raised into a hump, laterally defined by strongly raised longitudinal axillar carinae; and the costal margin of hind wing is not sclerotized as in S. braunsi .

Etymology.

Named in honour of John Midgley, who first collected specimens of the new species as part of his PhD project. Noun in the genitive case.

Distribution and habitat association

(Fig. 50 ). This species is currently only known from the Eastern Cape Province where it is associated with high altitude regions (1197-1805 m) across a variety of micro-habitats present in Camdebo Escarpment Thicket (Grassland biome), including open grassland, grassland with mixed thicket, mixed thicket with some small shrubs, larger trees and sparse grass, to Acacia thicket with medium or tall trees, either on steep rocky slopes or in flatter areas next to river courses. This vegetation type is restricted to the Eastern Cape Province. The following vegetation distributional summary was extracted verbatim from Mucina and Rutherford (2006):

Camdebo Escarpment Thicket (south-sloping face of the Great Escarpment, forming an arc from Bruintjieshoogte in the east via the Coetzeeberg Mountains and Graaff-Reinet (including Spandaukop and the isolated Rooiberg) to Kamdebooberg and Aberdeen in the west; altitude varies from 570-1600 m, with most of the area between 700-1200 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, but possibly restricted to higher altitudes in Camdebo Escarpment Thicket.

Figures

Figure 42. Sceliotrachelus karooensis van Noort, sp. nov. female paratype SEM photos (SAMC) (SAM-HYM-P 084755) A clypeus, mandibles, ventroanterior view B clypeus, mandibles, anterior view C occiput, pronotum, mesoscutum, lateral view D occiput, pronotum, lateroposterior view E mesopleuron, ventral view F mesopleuron, propodeum, ventrolateral view G mesopleuron, propodeum in part, lateral view H hind tibial spurs.

Figure 43. Sceliotrachelus midgleyi van Noort, sp. nov. female holotype (SAMC) (SAM-HYM-P 046650) A habitus, lateral view (inset: data labels) B habitus, dorsal view C head, mesosoma, lateral view D head, mesosoma, dorsal view E habitus, ventral view F metasoma, lateral view.

Figure 44. Sceliotrachelus midgleyi van Noort, sp. nov. female holotype (SAMC) (SAM-HYM-P 046650) A metasoma, ventral view B pronotum, mesoscutum, dorsolateral view C mesosoma, lateral view D occiput, dorsoposterior view E wings, dorsal view F wing setation detail, medial section.

Figure 45. Sceliotrachelus midgleyi van Noort, sp. nov. female paratype (SAMC) (SAM-HYM-P 036025) A habitus, lateral view B habitus, dorsal view C head, mesosoma, lateral view D head, mesosoma, dorsal view E head, anterior view D antenna, dorsolateral view.

Figure 46. Sceliotrachelus midgleyi van Noort, sp. nov. A, B female paratype (SAMC) (SAM-HYM-P 036025) C-F male paratype (SAMC) (SAM-HYM-P 040645 a) A propodeal, tergal and sternal foamy structures, lateral view B fore wing (inset: data labels) C habitus, dorsal view (inset: data labels) D head, anterior view E head, mesosoma, lateral view F head, mesosoma, dorsal view.

Figure 47. Sceliotrachelus midgleyi van Noort, sp. nov. A-C male paratype (SAMC) (SAM-HYM-P 036030) D-F female paratype (SAMC) (SAM-HYM-P 046654 B) A habitus, dorsal view B habitus, lateral view C habitus, ventral view D habitus, dorsal view E habitus, lateral view F habitus, ventral view.

Figure 48. Sceliotrachelus midgleyi van Noort, sp. nov. female paratype SEM photos (SAMC) (SAM-HYM-P 036030) A clypeus, mandibles, anterolateral view B occiput, dorso-posterior view C mesosoma, dorsal view D mesosoma, dorso-lateral view E mesopleuron, propodeum, T 1, lateral view F propodeum, hind coxa, T 1, dorsolateral view G T 1 - 2, dorsolateral 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).