Zetheumenidion concinnoide, Selis, 2024

Selis, Marco, 2024, Revision of the Afrotropical genus Zetheumenidion Bequaert (Hymenoptera: Vespidae: Eumeninae), Zootaxa 5406 (1), pp. 37-65 : 41-45

Zetheumenidion concinnoide sp. nov.

( Figs. 3 , 12 )

Diagnosis. Recognized by the following combination of characters: dorsal side of mesosoma not forming an even surface, pronotal carina evenly developed for whole length, anterior margin of pronotum straight, mesepisternum with dense small punctures, propodeum evenly sloping from metanotum to orifice and weakly convex, not bulging above valvula, dorsal faces of propodeum with microsculpted and matte ridge-like interspaces, T1 not expanded basally and of same height for whole length, apical lamella of T2 barely reflexed ( Fig. 3E ), male hind femur shiny and not shagreened on outer face and strongly swollen on ventral face ( Fig. 3D ), black and ferruginous-red pattern.

Material examined. HOLOTYPE: ♂ labeled “FOREST HILL / JOHANNESBURG / TVL. 18.12.61 / H. N. EMPEY // 1701 ♂ // Zetheumenidion / femoratum (Sch) / Giordani Soika det. 1982 // Zetheumenidion concinnoide / HOLOTYPUS ♂ / Det. Marco Selis ” ( MSNVE) . PARATYPES, SOUTH AFRICA: E. Transvaal, Elandshoek , 20– 25.XI.1947, leg. A.L. Capenet, 1♀ ( MSVI) ; Groenkloof , 19.XI.1921, leg. A. Roberts, 1♀ ( MSNVE) ; Johannesburg , Forest Hill, 18.XII.1961, leg. H.N. Empey, 2♀ ( MSNVE) ; Schoemanville , 16.II.1963, leg. H.N. Empey, 1♀ ( MSNVE) ; Transvaal , Benoni, 17.XII.1961, leg. H.N. Empey, 1♂ ( MSVI) ; Transvaal , Pretoria North, 19.X.1947, leg. C. Jacot-Guillarmod, 1♂ ( MSNVE) ; Transvaal , Swartkops, 19.X.1963, leg. H.N. Empey, 1♂ ( MSNVE) .

Description. Male holotype. Body length 12.0 mm; fore wing length 8.2 mm.

Head 1.3× as wide as long in frontal view ( Fig. 3B ). Clypeus 1.1× as long as wide in frontal view, apical margin shallowly but evenly emarginate and wider than interantennal space, 0.4× as wide as width of clypeus, apical angles more or less right-angled and pointed; clypeus in lateral view distinctly convex in basal half and then shallowly depressed, disc bulging. Interantennal space tuberculate above level of antennal toruli. Distance from posterior ocellus to occipital carina 1.55× as long as the distance from posterior ocellus to inner eye margin; vertex in lateral view weakly convex, shallowly concave along occipital carina; gena as wide as eye at bottom of ocular sinus; occipital carina complete, strong and shortly lamellate for whole length, more highly on gena. F1 2.45× as long as wide and 1.8× as long as F2; F2–5 distinctly longer than wide; F6–9 subquadrate to weakly transverse; F11 subconical and weakly curved at base, with strongly flattened apical half, reaching base of F9; F3–9 with weakly developed tyloids, linear on F3–8 and wide on F9. Mesosoma in dorsal view 1.2× as long as wide. Pronotum in dorsal view with converging sides; pronotal carina complete, forming a sharp translucent lamella on dorsal face; humeri rounded, obtuse in dorsal view; lateral faces short and markedly separated from dorsal face. Mesoscutum 0.8× as long as wide in dorsal view, weakly convex in lateral view. Scutellum almost flattened, anterior margin shallowly crenate on extreme sides and deeply furrowed in the middle. Metanotum weakly convex and oblique, distinctly produced in the middle of the posterior margin. Tegula with strongly convex surface and outer margin, maximum width in front of middle, posterior lobe acute-angled and apically rounded, not equaling parategula; parategula oblique and nearly straight in dorsal view, strongly flattened and forming a sharp vertical lamella. Mesepisternum weakly convex, sharply separated from epicnemium but without epicnemial carina. Propodeum oblique and weakly convex, mid-line evenly convex from metanotum to propodeal orifice; lateral face shallowly depressed, forming a shallow pit above anterodorsal angle of propodeal valvula; posterior face subtriangular and deeply concave above orifice; transition between dorsal and lateral carinae markedly angled but all carinae lacking; propodeal valvula about as long as basally wide and apically rounded. T 1 in dorsal view 4.6× as long as apically wide, sides weakly diverging in basal third, then weakly concave, width at level of spiracles about equal to apical width; T 1 in lateral view weakly and evenly expanded at extreme base, then of regular height to apex; dorsal face of T1 somewhat flattened on disc. T2 bell-shaped with basal petiole wider than long, preapical area strongly bulging and nearly sharp, apical lamella preceded by a costulate depressed area, then barely reflexed; T 2 in lateral view strongly convex behind basal petiole. S2 much less convex than T2, apical margin lamellate similar to T2, but preapical area shallowly bulging and rounded, and apical lamella shorter and not reflexed. T3 with a somewhat decolorate apical margin, but not lamellate. T7 weakly and evenly convex; S7 evenly rounded and wide, mostly flattened. Hind femur enlarged, in lateral view 2.8× as long as wide and with dorsal margin weakly convex and ventral margin strongly convex with sinuate base, ventral face with an obliquely depressed elliptical area in basal half and a centrally placed spine-bearing pore ( Fig. 3D ).

Clypeus deeply punctured, each puncture having a central deep pore from which a seta arise, interspaces everywhere narrower than puncture diameter, more strongly on disc. Head very deeply and densely punctured, punctures smaller on frons and becoming larger and slightly sparser on vertex, interspaces narrower than puncture diameter and convex and shiny; gena more sparsely punctured, interspaces shiny; area along occipital carina finely and sparsely crenate. Dorsal face of mesosoma with deep punctures larger than those on vertex, interspaces flattened and about half as wide as puncture diameter; some interspaces on scutellum reaching one puncture diameter in width. Tegula shiny with few sparse large punctures. Mesepisternum with smaller but coarser punctures, several punctures touching each other and forming irregular series. Metaepisternum with fine transverse striae on upper plate, sparse deep punctures on lower plate. Dorsal faces of propodeum very densely punctured, interspaces shagreened and matte, mostly reduced to sharp ridges; posterior face of propodeum with irregular transverse striae and small deep punctures; lateral face of propodeum with sparse and fine but strong striation, with few small punctures mixed, striae becoming finer around apical pit. T1 with small deep punctures, interspaces ranging from half to several puncture diameters, very finely and shallowly shagreened on whole surface, densely but shallowly micropunctate on disc. T2 densely shagreened and matte, macropunctures almost invisible basally and becoming progressively larger and deeper apically, with a series of coarse punctures in front of the preapical bulge. T3–7 shagreened with very fine micropunctures, T7 with few sparse punctures. S2 more shiny than T2, punctures deep and sparse and becoming progressively stronger apically. S3–7 similar to respective tergites, S7 with sparse small fine punctures. Outer face of hind femur shiny with sparse punctures becoming deeper and larger apically. Frons with long pale setae, longer than ocellar diameter; clypeus, gena and mesosoma with shorter pale setae; sides of propodeum with dense fine whitish setae; metasoma with very short grayish pubescence, short erect setae at base of T1 and at apex of S2–6, S7 with longer darker setae forming a sparse preapical brush.

Black; following parts ferruginous-red: most of mandible, antenna from scape to F5, pronotum, tegula, parategula, scutellum, metanotum, dorsal faces of propodeum except basal and median margins, upper plate of mesepisternum, sides and preapical band on T1, T2 except large triangular median spot, S2 except median longitudinal band slightly exceeding middle, legs except basal half of ventral face of hind femur; following parts pale yellow: clypeus, ventral face of scape, outer face of all tibiae and basitarsi; following parts bright yellow to yellow-orange: inner margin of eye up to ocular sinus, narrow anterior margin of pronotum, spot on posterior margin of upper plate of mesepisternum, suffused apical margin of T1, apical margin of T2 and S2; F8–10 with contrasting ivory spot on ventral face. Wings weakly infuscate with brassy reflections in basal half, more strongly infuscate with purplish reflections in apical half.

Female. Differing from male as follows: clypeus as long as wide and more irregularly punctate, apical margin subtruncate and 0.35× as wide as width of clypeus ( Fig. 3C ); vertex with cephalic foveae, closer to occipital carina than to ocellar triangle and separated by less than their diameter, bearing a small tuft of very short dark brownish setae; propodeum less convex and nearly vertical, with shallower posterior depression; hind femur not enlarged, shallowly concave on ventral face and weakly curved; all markings ferruginous-red, except for ivory line on posterior face of hind tibia.

Variability. All examined specimens are remarkably constant in size (body length 12.3–15.5 mm in ♀ and 11.2–12.3 mm in ♂), morphology and pattern. One female from Forest Hill as weakly yellowish anterior margin of pronotum, one female from Groenkloof has brighter apical band on T2 and sparser sculpture on clypeus, and one male from Pretoria North has sparse punctures on clypeus.

Distribution. South Africa: Eastern Cape, Free State, Gauteng, Mpumalanga, North West ( Bequaert 1926 [as Zetheumenidion femoratum ]; Giordani Soika 1983 [as Zetheumenidion femoratum ]) ( Fig. 13 ).

Etymology. The species epithet refers to the pattern of this species, which forms a mimicry ring with Delta concinnum (de Saussure) .

Notes. As argued below, most of the records of Zetheumenidion femoratum published by Bequaert (1926) and Giordani Soika (1983) are to be referred to Z. concinnoide .

Figures

FIGURE 3. Zetheumenidion concinnoide sp. nov. A, male habitus in dorsal view. B, male head in frontal view. C, female head in frontal view. D, male hind femur in lateral view. E, female metasoma in lateral view.

FIGURE 12. Male genitalia of Zetheumenidion species: aedeagus in ventral view, aedeagus in lateral view and digitus + volsella.

FIGURE 13. Distribution maps of Zetheumenidion species.