Virgichneumon digrammus (GRAVENHORST, 1820)

Riedel, Matthias, 2024, The genus Virgichneumon HEINRICH in the West Palaearctic region (Hymenoptera, Ichneumonidae, Ichneumoninae), Linzer biologische Beiträge 56 (1), pp. 149-199 : 161-162

Virgichneumon digrammus (GRAVENHORST, 1820) (figs 4, 26, 46, 64, 83, 97)

Holotype: (♁) (Wroclaw), studied and comb. nov. by RASNITSYN (1981).

D e s c r i p t i o n: ♀. Body length 7.0-9.0 mm. Flagellum with 34-36 segments, slightly lanceolate; 1 st flagellar segment 1.9-2.1× as long as wide, 5 th or 6 th segments square, widest segments 1.2× as wide as long. Temple distinctly and almost linearly narrowed behind eye (fig. 4). OED 1.1-1.4× and OOD 1.5-1.8× ocellar diameter. Gena coarsely striate-punctate, with finer sparse punctures ventrally, about as wide as eye (fig. 83). MI 1.0. Hypostomal carina slightly elevated.

Epicnemial carina slightly elevated behind fore coxa. Scutellum wider than long, with sparse punctures. Area superomedia heart-shaped, slightly longer than wide; at or slightly posterior to its middle with costula (fig. 26). Hind coxa densely punctate, without scopa. Hind femur densely punctate, 3.4-3.6× as long as wide. External surface of hind tibia with several (5-6) denticular spines. Areolet pentagonal, frontal distance between veins 2rs-m and 3rs-m 1-2× their width; vein 2m-cu reaching distad its middle; vein 1cu-a postfurcal.

Postpetiole with latero-median carina; median field elevated, densely punctate and often with some longitudinal rugae. Gastrocoelus impressed, with ridges. Thyridium slightly oblique, 0.5× as wide as interval between thyridia (fig. 46). 2 nd tergite 1.4× as wide as long; 2 nd and 3 rd tergites densely punctate, 2 nd tergite ± rugose medially (fig. 46). Ovipositor sheath extending beyond metasomal apex by length of 3 rd hind tarsomere.

Color: black. Setae of mesoscutum brownish. Flagellar segments 8/10-13/14 dorsally, narrow frontal orbit, entire scutellum, and dorsal spot of 7 th tergite, sometimes also narrow hind margin of 6 th tergite, ivory. Coxae and trochanters black (sometimes diffusely reddish); legs otherwise red; hind tibia in apical 0.1-0.3 and hind tarsus blackish. Wings slightly infuscate, pterostigma black or dark brown.

♁. Body length 8.0-10.0 mm. Flagellum with 35-38 segments, bristle-shaped, distal segments ± nodose; 1 st flagellar segment 2.6× as long as wide. Tyloids on flagellar segments 6/7-15/17, oval, maximally 0.7-0.8× as long as their segments (fig. 97). Temple strongly and roundly narrowed behind eye. OED 1.0-1.1× and OOD 1.6× ocellar diameter. Fore metatarsus with weak apical tooth. Hind femur 3.5-3.8× as long as wide.

2 nd tergite 0.9-1.1× as long as wide. Postpetiole and 2 nd tergite densely punctate, 2 nd tergite sometimes rugose-punctate basally.

Color: black. Flagellum black, ± reddish ventrally. Palps, clypeus laterally, inner orbit up to lateral ocellus (fig. 64), collar and upper margin of pronotum ±, spots of tegula and subtegular ridge, and apical 2/3 of scutellum ivory or yellowish. Coxae and trochanters black; legs otherwise reddish; hind femur often ± infuscate apically, sometimes entirely black); hind tibia in apical 0.3-0.5 and hind tarsus entirely black. Pterostigma brownish.

T a x o n o m i c a l r e m a r k s: The ♁♁ with black hind femora are easily confused with the ♁♁ of V. dumeticola (GRAVENHORST) . They differ slightly by the form of tyloids (oval and shorter than their flagellar segments, fig. 97) and darker base of hind tibia.

S t u d i e d m a t e r i a l: from Germany, Greece: Crete * (Linz), Italy, Russia, Spain, Sweden, Turkey.