Alastor (Alastor) gestroides Selis, 2020

Selis, Marco, 2020, Notes on the Afrotropical species of Alastor Lepeletier (Hymenoptera: Vespidae Eumeninae), with description of nine new species, Zootaxa 4822 (3), pp. 361-388 : 367-370

Alastor (Alastor) gestroides Selis , sp. nov.

( Figs. 10–14 , 44 )

Diagnosis. This species comes close to Alastor (A.) gestroi Giordani Soika in having elongate antennae with convex flagellomeres, wide clypeus with short free apical margin, pronotal carina complete and humeri extended in flattened tubercles, punctured tegula and small T1, it is differentiated by the following characters: apical margin of clypeus weakly rounded out ( Fig. 11 ), F1 about as long as F2, F 11 in lateral view flattened and not convex above ( Fig. 12 ), humeri less pronounced and sides of dorsal face of pronotum not concave ( Fig. 13 ), tegula more strongly punctured and with wider posterior lobe, metanotum flattened, T2 about as long as wide ( Fig. 14 ), punctures on head and mesosoma larger and deeper, interspaces larger and flattened, punctures on metasoma deeper, those on T2 sparse.

Material examined. Holotypus, ♂, labeled “ CAPE PROVINCE / Grahamstown / 29-XI-1964 / D.J. Brothers // Alastor (A.) gestroides / Selis, sp. nov. / HOLOTYPUS ♂ / Det. Marco Selis 2018” ( MSNVE) .

Description. Holotype, male ( Fig. 10 ). Body length 7.3 mm; fore wing length 5.8 mm.

Head in frontal view 1.2 × as wide as long ( Fig. 11 ), in dorsal view about as wide as mesosoma. Clypeus in frontal view 1.3 × as wide as long, dorsal margin convex, lateral margins of free apical part weakly convex and forming a subrectangular produced apical portion, apical margin about as large as interantennal space and weakly rounded out, 0.2 × as wide as clypeus width, apical angles obtuse and rounded; clypeus in lateral view convex basally. Interantennal space weakly convex. Vertex long, distance from posterior ocellus to occipital margin 1.2 × as long as distance from posterior ocellus to inner eye margin, about as long as dorsal lobe of eye; gena in lateral view about as long as width of eye at bottom of ocular sinus; occipital carina complete but indistinct dorsally, lamellate ventrally and strongly angled at height of basal third of clypeus. Scape 2.6 × as long as apically wide; F1 1.7 × as long as wide and about as long as F2; F2–F9 distinctly longer than wide, convex above and weakly concave below; F10 small, subquadrate; F11 short and reaching base of F9, in dorsal view parallel sided with rounded apex, in lateral view narrow and evenly tapering to the apex ( Fig. 12 ). Mandible elongate and curved, 5-toothed, three apical teeth pointing downward, fourth tooth large and triangular, perpendicular to mandibular axis, fifth tooth wide and short, apically rounded. Mesosoma in dorsal view 1.3 × as long as wide. Pronotal carina complete and strong, shortly lamellate on dorsal face and continued behind by a short oblique humeral carina; humeri in dorsal view weakly pointing out, nearly right-angled, sides of pronotum converging anteriorly, when viewed from the front humeri projects as flattened tubercles; lateral faces of pronotum depressed ( Fig. 13 ). Mesoscutum in dorsal view 1.1 × as wide as long, weakly convex in lateral view. Scutellum weakly oblique, flattened on disc and with a very shallow median longitudinal furrow. Metanotum entirely vertical, entirely flattened. Mesepisternum weakly convex above, more convex ventrally, lamellate along foramen, epicnemial carina absent. Propodeum in dorsal view about as long as scutellum, broader than long, with strongly curved lateral margins and sharp conical apical teeth pointing behind; median depression of posterior face moderately deep, occupying median third of propodeum, median triangular area short and not reaching mid length of propodeum; when propodeum in lateral view, dorsal margin oblique and flattened, apical teeth pointing behind. Tegula broader in anterior third, outer margin strongly convex anteriorly, more weakly posteriorly and shortly reflexed, posterior lobe short and triangular, rounded apically, surface very weakly convex. T 1 in dorsal view weakly elongate and anteriorly rounded, 1.6 × as long as broad; in lateral view anterior face oblique and weakly convex, forming an obtuse rounded angle with horizontal face, which is occupied by a shallow and broad preapical furrow, apical margin weakly inflated. T 2 in dorsal view 1.15 × as wide as long, with anteriorly rounded sides, 1.55 × as wide as width of T1 ( Fig. 14 ); T 2 in lateral view distinctly convex for entire length. S2 weakly shorter than T2, in lateral view weakly and evenly convex from base to apex.

Clypeus densely punctured, interspaces narrower than punctures diameter, roundly raised and shiny. Frons and vertex with deep punctures, interspaces shorter than punctures diameter and strongly shiny; gena punctured similar to vertex but punctures smaller and interspaces larger. Mandible smooth with some shallow punctures in basal triangular area. Scape with small deep punctures, interspaces weakly larger than punctures diameter. Anterior face of pronotum smooth, with few deep punctures on extreme sides; dorsal face of pronotum with large deep punctures, becoming shallower on anterior margin, interspaces flattened and shiny, as large as or shorter than punctures diameter; lateral faces of pronotum irregularly sculptured. Mesoscutum punctured like pronotum, but interspaces very narrow and irregular posteriorly. Scutellum with punctures similar to mesoscutum, but smaller and sparser, interspaces shiny and flattened, with some micropunctures. Metanotum largely smooth and shiny, with coarse punctures on anterior corners. Proepisternum shiny and micropunctate, with coarse deep punctures on posterolateral corner. Mesepisternum with deep dense punctures forming irregular series, interspaces very narrow and opaque; epicnemium densely micropunctate and with deep large punctures ventrally. Dorsal plate of metaepisternum with strong transverse striae dorsally, ventral corner smooth; ventral plate of metaepisternum microreticulate and weakly shiny, with some sparse deep punctures. Dorsal faces of propodeum deeply punctured, interspace shiny and variable in size, from larger than punctures diameter to very narrow; median depression of propodeum smooth and shiny with shallow punctures on extreme sides; lateral faces of propodeum punctured like dorsal faces, but interspaces dull. T1 smooth and weakly shiny, punctures fine and shallow on anterior vertical face, a little deeper dorsally and becoming large and deep on sides, punctures not covering apical inflated margin. T2 with deep irregular punctures, interspaces shiny and variable in size, much larger than punctures diameter basally and on disc, becoming shorter on sides and apically. T3–T6 microreticulate and dull, punctures on T3 deep and dense with interspaces about as large as punctures diameter, punctation of following terga becoming shallower and sparser. T7 shiny, with some indistinct punctures on sides. S1 densely and deeply punctured, interspaces smooth and shiny, shorter than punctures diameter. S2 with punctures deeper and larger than respective tergum, interspaces large and strongly shiny. S3–S6 sculpted like respective terga, but punctures sparser. S7 shiny with dense fine small punctures.

Upper side of head and mesosoma with long gold setae; basal third and sides of clypeus, mesepisternum, propodeum and T1 with short silvery pubescence; metasoma with dust like grayish pubescence, giving it a sericeous shine, some short setae on S3–S7.

Apical part of aedeagus in ventral view subtriangular, with ventral lobes pointing out, sides converging apically with fusiform median third, apex rounded and weakly expanded; in lateral view with dorsal margin straight and curving only at extreme apex, ventral margin smoothly continuing from right angled ventral lobe of penis valve, sinuate in basal two thirds, then concave, basal half of ventral margin finely serrate. Basal plate of aedeagus short and triangular. Basal apodeme of aedeagus in lateral view long and narrow, evenly curved with pointed apex, low lamellar expansion near middle of ventral margin; basal apodemes in ventral view diverging in basal half, then converging ( Fig. 44 ). Distal lobe of digitus long, subrectangular with parallel sides, apex rounded and weakly expanded, ventral margin weakly sinuous; basal lobe of digitus long and rounded, forming a more or less right angle with rest of digitus; ventral root of digitus long and pointed. Long sparse setae on basal two thirds of digitus; tubercles in the middle of digitus and expanding on basal lobe. Volsella moderately setose, cuspis triangular and sharply pointed; tubercles on area near articulation with digitus.

Black; following parts pale yellow: clypeus, mandibles except margins, underside of scape, spot at bottom of ocular sinus, transverse triangular markings on humeri, inflated apical margin of T1, laterally enlarged apical band on T2, narrow apical band on T3 not reaching sides, bisinuate apical band on S2, apical half of outer face of fore and mid femora, indistinct basal marking on fore tibia, outer surface of mid and hind tibiae; following parts ferruginous: median third and posterior margin of pronotum, tegula, most of fore leg, apical half of mid femur, all tarsi. Wings weakly smoky, more on costal margin.

Etymology. The specific name is in reference to the resemblance of this new species to Alastor (A.) gestroi .

Distribution. South Africa: Eastern Cape.

Figures

FIGURES 10–14. Alastor (Alastor) gestroides Selis, sp. nov., ♂. 10, Habitus in dorsal view. 11, Head in frontal view. 12, Flag- ellum in lateral view. 13, Pronotum in lateral view. 14, Metasoma in dorsal view.

FIGURES 43–48. Aedeagus in lateral and ventral view. 43, Alastor (Alastor) brevicornis Selis, sp. nov. 44, Alastor (Alastor) gestroides Selis, sp. nov. 45, Alastor (Alastor) moody Selis, sp. nov. 46, Alastor (Alastor) namibiensis Selis, sp. nov. 47, Alastor (Alastor) parilis Selis, sp. nov. 48, Alastor (Alastor) temperatus Selis, sp. nov.