Virgichneumon stegemanni ( Heinrich, 1934 ) Riedel, 2023

Riedel, Matthias, 2023, Contribution to the knowledge of the Ichneumoninae (Hymenoptera, Ichneumonidae) from Maritime Southeast Asia, Zootaxa 5363 (1), pp. 1-94 : 91

Virgichneumon stegemanni ( Heinrich, 1934) nov. stat.

( Figs 41A–C )

Material. Indonesia: SE Sulawesi, nr Sanggona, Base camp, Gn. Watuwila, Mal. trap 1, c 225 m, 1 ♂ 15.x. – 5.xi.1989, leg. C. van Achterberg; N Sulawesi, Dumoga-Bone N.P., c 220 m, Mal. trap: Maze Toraut R., 0°34´N 123°54´E, 1 ♂ 1–9.xi.1985, leg. C. van Achterberg (Leiden) .

Description. ♂. Body length 9–10 mm.

Head. Flagellum with 32–34 flagellomeres, bristle-shaped; 1 st flagellomere 1.9 × longer than wide, distal flagellomeres ± nodose. Tyloids on flagellomeres 9–14, long-oval, maximally 0.6 × as long as their flagellomeres. Temple short, strongly and roundly narrowed behind eye. OED 1.2 × and OOD 1.2 × ocellar diameter. Face wide and short, densely punctate (fig. 41A). Clypeus slightly convex, densely punctate; apical margin blunt, slightly rounded. Mandible with two teeth, ventral tooth much smaller and slightly bent inwards. Malar space 0.5 × as long as width of mandibular base. Genal carina reaching hypostomal carina close to mandibular base.

Mesosoma . Notaulus distinct in frontal 0.2 of mesoscutum. Mesoscutum densely punctate, shining. Mesopleuron and metapleuron densely punctate, speculum smooth; juxtacoxal carina present. Scutellum moderately elevated, slightly wider than long, with rather dense punctures, without lateral carina. Propodeum completely carinated, without apophysis (fig. 41B); spiracle slit-shaped. Area basalis 3.0 × wider than long, moderately bulging forward medially. Area superomedia hexagonal, c 1.5–2.0 × wider than long; costula reaching at 6/10 of its length. Hind femur 4.0 × longer than wide. Areolet almost quadrangular, frontal distance of veins 2rs-m and 3rs-m 1.0 × their width. Vein 1cu-a postfurcal by 2.0 × its width.

Metasoma. Postpetiole moderately widened, with strong latero-median carina; median field moderately elevated, with coarse and dense punctuation (fig. 41C). 2 nd tergite 1.1 × wider than long. Gastrocoelus distinctly impressed, with lateral ridge. Thyridium slightly oblique, 1.1 × wider than the interval between thyridia. 2 nd to 4 th tergites coarsely rugose-punctate; 2 nd and 3 rd tergite ± striate medially.

Colour. Black. Flagellum black, reddish ventrally. Palps ivory. Yellow are mandible except teeth, clypeus, face, gena, stripes on outer, frontal and vertical orbits, scape ventrally, propleuron ventrally, collar and upper margins of pronotum, tegula, subtegular ridge, short paramedian stripes on mesoscutum, wide band at ventral mesopleuron, scutellum except reddish central stripe, area dentipara, and posterolateral spot on postpetiole. 1 st to 5 th tergites red, sometimes 5 th tergite partly brownish; 6 th and 7 th tergites blackish, sometimes with narrow yellowish apical margins, paramere brown. Legs red; fore and mid coxae and trochanters and dorsal spot of hind coxa ivory; hind femur sometimes narrowly black apically. Wings hyaline; pterostigma ochreous or brown.

Remarks. The species was described as a member of Intermedichneumon Heinrich by Heinrich (1934) and catalogued in that genus by Gupta (1988) but transferred to Vulgichneumon Heinrich by Heinrich (1967). It differs from typical members of Intermedichneumon by the coarse punctuation and distinct latero-median carina of the postpetiole, and from Vulgichneumon ♂♂ by the large and subbasally located thyridia. Therefore, this species is transferred to Virgichneumon Heinrich here, a genus which is new for the Oriental region.

Distribution. Only known from Sulawesi.

Figures

FIGURE 41. Virgichneumon stegemanni (Heinrich, 1934) ♂. A face, frontal view, B propodeum, frontal view, C basal tergites, frontal view.