Plesianthidium (Spinanthidium) trachusiforme (Friese)

(Figs 16–18)

Anthidium trachusiforme Friese, 1913a: 595 (holotype—‘1 ♀Ookiep (Klein-Namaland) im September fliegend’ (ZMHB, examined) South Africa).

Spinanthidium (Spinanthidium) trachusiforme: Pasteels 1969: 55, 59.

Dianthidium trachusiforme: Cockerell 1921: 209 .

Plesianthidium (Spinanthidium) trachusiforme: Gess et al. 1997: 84 .

Anthidium trispinosum Friese, 1925: 510 (holotype—‘♂ von Giftsberg, Rhynsdorp (Kapland), Septbr. 1911’ (ZMHB, examined) South Africa), synonymised by Mavromoustakis (1951).

Discussion. Anthidium trispinosum was synonymised with trachusiforme by Mavromoustakis (1951: 977). Pasteels (1984) did not include this species, possibly because it is a junior homonym of Anthidium trispinosum (Friese 1917) . Synonymy is confirmed by the study of the type.

Diagnosis. The female can be distinguished from all other Plesianthidium by the unique form of the clypeus in which the ventral margin is strongly concave between a pair of projecting spines (Fig. 16 c). Males are recognizable by the combination of a rounded preoccipital ridge, white to yellow vestiture (not largely orange or black), paraocular area yellow in part (Fig. 16 e), tergal integument entirely dark, T7 tridentate with long lateral spines (Figs 17 a, b) and S4 without an apical comb. The structure of S6–S8 (Figs 17 c–e) are diagnostic.

Within the subgenus Spinanthidium, P. trachusiforme is most like P. calescens, with which it shares the black distal margins of the metsomal terga. It differs in the presence of yellow maculations on the paraocular area and the absence of an apical comb on S4. The male S8 is unique (Fig. 17 e).

Description. Female. Lengths: face 3.2–3.6 mm; scutum 2.4–2.6 mm; forewing 9.8– 8.3 mm; body 9.0– 9.5 mm. Integument entirely black. Vestiture generally white, mesosoma pale yellow below, yellowish and orange above (Fig. 16 a); scopa pale yellow anteriorly, orange posteriorly. Metasomal terga without distal fasciae. Preoccipital ridge rounded; distance between lateral ocellus and preoccipital ridge twice ocellar diameter; supraclypeus convex; clypeus flattish, ventrally with distinct spine mediolaterally, deeply concave between spines, sparsely punctate; mandible black, with two distinct teeth and three small teeth; maxillary palpus 2-segmented; scutum densely punctate, dull between punctures; tegula densely punctate medially; propodeum mostly punctate; legs black; T2–T3 without distal fasciae, punctate distally; T6 slightly expanded laterally, distinctly expanded posterolaterally, without mediolongitudinal carina.

Male. Lengths: face 3.0– 3.5 mm; scutum 2.3–3.0 mm; forewing 7.9–10.5 mm; body 7.4–11.6 mm. Integument black, except clypeus yellow and lower paraocular areas yellow or occasionally partly yellow (Fig. 16 e). The vestiture is generally white, mesosoma pale yellow below, and yellowish and orange above (Figs 16 d, e). Preoccipital ridge rounded; distance between lateral ocellus and preoccipital ridge twice ocellar diameter; supraclypeus distinctly convex; clypeus distinctly convex, densely punctate; mandible with three distinct teeth; maxillary palpus 2-segmented; scutum densely punctate medially, dull between punctures; tegula densely punctate; propodeum mostly punctate; hind trochanter without a ventral spine; T2–T5 without distal fasciae; T6 without mediolongitudinal carina, with large posteromedial tubercle, with distinct lateral spines, without impunctate distal margin, without distal flange (Fig. 17 a); T7 posterior edge tridentate with moderately large lateral and median teeth, all spines narrow, median blunt, lateral pointed (Figs 17 a, b); S4 without apicomedian comb; S5 posterior edge shallowly concave; S6 broadly convex with posteromedian truncation (Fig. 17 c); S7 disc short, with broad, distinct posterior concavity (Fig. 17 d); S8 disc short and broad, with small truncate protuberance posteromedially (Fig. 17 e); gonostylus concave apicolaterally (Fig. 17 f).

Distribution (Fig. 18). Plesianthidium trachusiforme is almost exclusively known from Namaqualand. In this study there is one specimen that was collected in the South-Western Cape and two unexpected records, one from Grahamstown, in the Eastern Cape Province of South Africa, and the other from Mt Selinda in Zimbabwe, both of which are questionable.

Associated plants. Anchusa capensis, Aspalathus linearis, Aspalathus spinescens, Ballota africana, Berkheya fruticosa, Heliophila sp., Hermannia disermifolia, Hermannia cf. disermifolia, Hermannia trifurca, Hermannia sp., Herrea sp., Hirpicium alienatum, Indigofera spinescens, Lebeckia sericea, Lebeckia sp., Melolobium candicans, Pteronia incana, Wiborgia monoptera, Zygophyllum meyeri and an unidentified Fabaceae .

Material examined. Type material. Female holotype of Anthidium trachusiforme Friese: ‘Kl. Namaland O’okiep ix.1900, Anthidium trachusiforme ♀Fr. 1913 Friese det., Spinanthidium trachusiforme Fr. J. Pasteels det., 1963, Holo Typus’, in ZMHB. Male holotype of Anthidium trispinosum Friese: ‘Giftsberg Rhynsdorp C.C. Sept. 1911, Anthidium trispinosum ♂ n. Fr., Type, Spinanthidium trispinosum Fr. J. Pasteels det., 1963, Syn, Anthidium trispinosum HOLOTYPE R. Urban 2005’, in ZMHB.

Additional material. Zimbabwe. Mt Selinda, 20.25S 32.43E, 1954. ii.10, N.J. Myers (1♂ AMGC 2950) (doubtful record). South Africa. O’okiep, 29.6082S 17.91666E,1987. ix.13, C.D. Eardley, (1♂ SANC 04047); O'okiep, 3 km W, 29.6082S 17.8608E, 2008. x.15, T.L. Griswold (2♀ 1♂ BLCU- 752473, 752474, 752475); Concordia, 4 km N, 29.5009S 17.9383E, 2008. x.15, T.L. Griswold, on Fabaceae sp. (1♀ 1♂ BLCU 752398, 752399); Narap, (Narab), 29.53S 17.46E, 1989. x.14, F.W. Gess (1♀ AMGC 2922); Taaiboskraal and Anegas, between, 30.07S 18.01E, 1995. x.03, F.W. Gess (1♀ 1♂ AMGC 2944); Goegap Nature Reserve, 1985. vii.20–ix.18– 23, 1986. ix.2–27, 1987. vii.31–x.4, M. Struck, (6♀ 12♂ SANC 0 4043, 19321, 0 8048, 0 4045, 0 4046, 0 4044, 0 8050, 0 4042, 0 4055, 0 4048, 0 4045, 0 4043, 0 4038, BLCU- 724912, 724916, SAMC 0 0 6913, 006914); idem, 1989. x.10– 11, F.W. Gess (1♂ AMGC 2945); Goegap Nature Reserve (hills), 29.38S 17.59E, 1987. ix.5, 1989. x.10–11, 1992. ix.8–10, F.W. Gess (6♀ 7♂ AMGC 2923. 2924, 2925, 2926, 2927, 2928, 2929, 2930, 2931, 2945); Goegap Nature Reserve (windmill), 29.37S 17.59E, 1994. x.4–8, 1995. ix.27, F.W. Gess (4♀ AMGC 2937, 2938, 2940, 2939); Klip Vlei, Garies, 1931. xi.1 (2♂ SAMC 004429); Garies, 1930. vii.1, Hesse (2♀ SAMC 006927); Arkeop farm, Kamieskroon, 6 km N, 30.19S 17.56E, 1990. x.1–2, C.D. Eardley (1♂ BLCU 724910); E Kamieskroon, 2.xi.1999, M. Snizek (1♀SC); Bowesdorp, 1931. xi.1 (3♀ 2♂ SAMC 004427); Dassiefontein farm,1990. x.1, C.D. Eardley (19♀ 60♂ SANC 0 4032, BLCU 724906, 724907, 724908, 724913, 724914); Kamieskroon, 1930. ix.1 (5♀ 9♂ SAMC 0 0 4410, 004428); Kamiesberg Pass, 31.12S 17.59E, 1987. ix.11, 2012. ix.15, C.D. Eardley (2♂ SANC 19319, BLCU 724911); Sors Sors, 9 km NE Kamieskroon, 30.10S 18.1E, 1992. ix.12–17, 1997. x.9–12, F.W. Gess (2♀ 3♂ AMGC 2932, 2933, 2936, 2946, 2949); Kamiesberg, 2 km S Leliefontein, 30.20S 18.5E, 1992. ix.13, F.W. Gess (1♀ AMGC 2934); Bakleikraal, Kamieskroon, 30.13S 18.03E, 1994. x.9, F.W. Gess (1♀ AMGC 2941); Leliefontein, 30.19S 18.05E, 1995. x.2, F.W. Gess (1♂ AMGC 2948); Groenekloof, 7.5 km SE Leliefontein, 30.22S 18.07E, 1992. ix.13, 1997. x.12, F.W. Gess (2♂ AMGC 2935, 2947); Leliefontein, 5 km Groenkloof road, 30.21S 18.07E, 1995. x.2, F.W. Gess (2♀ 2♂ AMGC 2942, 2943); Botterkloof Pass, dunes, 31.8127S 19.2647E, 2002. x.11, F.D. Parker (1♀ BLCU 724917); Knersvlakte, 1941. ix.1 (1♀ SAMC 004449); Nieuwoudtville Falls, 5 km N Nieuwoudtville, 31.19S 19.07E, 1990. ix.28, F.W. Gess (1♂ AMGC 2915); idem, 2004. ix.2, C.D. Eardley (1♀ SANC 12281); Witwater, 30.2319S 18 135239E, 29.v.2003, 2.x.2004, C. Mayer (4♀KC); Papkuilsfontein farm, 20km S Nieuwoudtville, 31.33.16S 19.08.31 E, 7.ix.2007, M. Kuhlmann (2♀ 4♂ KC); Avontuur farm, 12 km NW Nieuwoudtville, 31.16.18S 19.02.55 E, 19.ix.2009, M. Kuhlmann (1♀KC); Nieuwoudtville Flower Reserve, 31.22.18S 19.08.58 E, 19.x.2006, M. Kuhlmann (1♀ 1♂ KC); Keiski Mountains, 5 km S farm Nooiensrivier, 31.45.47S 19.50.17E, 12.ix.2010, M. Kuhlmann (1 ♀KC); Engelspunt, near, 31.14.08S 18.58.23E, 8.x.2003, K. Timmermann (1♂ KC); Nieuwoudtville and top Vanrhyns Pass, between, 31.22S 19.01E, 1990. ix.29–30, F.W. Gess (1♀ AMGC 2916); Nieuwoudtville, 13.5 km N, 31.2744S 19.1458E, 2007. ix.18, T.L. Griswold (1♂ BLCU 722349); Gifberg Pass, 31.7762S 18.7639E, 2008. x.17, T.L. Griswold, On Lebeckia sp. (1♂ BLCU 751943); Ysterfontein, 11 km W Clanwilliam Graafwater road, 32.10S 18.47E, 1990. x.2–8, F.W. Gess (1♂ AMGC 2917); Piekenierskloof, Paleisheuwel, 32.37S 18.57E, 1990. x.6, F.W. Gess (1♀ 3♂ AMGC 2918, 2919, 2920, 2921); Biedouw Valley, Clanwilliam 32.1333S 19.23333E, 1987. ix.5–7, C.D. Eardley (1♀ 4♂ SANC 0 4037, BLCU- 724909, 724915); Pakhuis Pass, East side, 32.1497S 19.0277E, 2004. x.5, M.E. Irwin F.D. Parker M. Hauser (1♀FDP 752968); Graafwater, 7 km W, 32.1505S 18.5314E, 2008. x.16, T.L. Griswold (1♂ BLCU 751868); Olifants River, between Citrusdal and Clanwilliam, 1931. x.1–1931. xi.1 (1♂ SAMC 004398); Montegu, 1919. x.1, Tucker (1♀ SAMC 004399); Strowan, Grahamstown, 33.17S 26.28E, 1969. x.22, F.W. Gess (1♀ AMGC 2914) (doubtful record).