Virgichneumon tergenus (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 : 177-178

Virgichneumon tergenus (GRAVENHORST, 1820) (figs 18, 40, 75, 91, 96)

Types lost.

D e s c r i p t i o n: ♀. Body length 8.5-10.0 mm. Flagellum with 31-32 segments, slightly lanceolate; 1 st flagellar segment 2.1-2.3× as long as wide, 6 th or 7 th segment square, widest segments 1.2-1.3× as wide as long. Temple strongly and almost linearly narrowed behind eye (fig. 18). OED 1.3-1.5× and OOD 1.7-2.0× ocellar diameter. Frons coarsely punctate. Face ± medially protruding. Clypeus with sparse punctures. Gena in profile 1.0-1.2× as wide as eye, widest at the junction of genal and hypostomal carinae, with sparse punctures ventrally (fig. 91). MI 1.1-1.2. Hypostomal carina slightly elevated.

Mesoscutum coarsely punctate, shining. Scutellum slightly wider than long, with sparse punctures and with lateral carina in basal 0.3. Epicnemial carina low behind fore coxa. Scutellum slightly wider than long, punctate, lateral carina in basal 0.4. Area superomedia heart-shaped, about as long as wide; at or slightly posterior to its middle with costula (fig. 40). Hind coxa densely punctate, without scopa. Hind femur densely punctate, 3.6-3.8× as long as wide. External surface of hind tibia with several (5-8) denticular spines. Areolet pentagonal, frontal distance between veins 2rs-m and 3rs-m 2- 3× their width; vein 2m-cu reaching almost at its middle. Vein 1cu-a postfurcal by 2× its width.

Postpetiole with distinct latero-median carina; median field elevated and densely punctate, sometimes with some longitudinal rugae. Gastrocoelus rectangularly impressed, with ridges. Thyridium small, 0.4× as wide as interval between thyridia. 2 nd tergite 1.4-1.5× as wide as long. 2 nd and 3 rd tergites densely punctate, smooth and shining between punctures, rarely 2 nd tergite with some rugae between gastrocoeli. Ovipositor sheath extending beyond metasomal apex by length of 7 th tergite.

Color: black. Setae of mesoscutum grey. Palps, flagellar segments 8-12 dorsally, spot on vertex opposite to lateral ocellus, and wide apical spots on 6 th and 7 th tergites ivory. Apical half of 1 st tergite, 2 nd to 4 th tergites entirely, sometimes 5 th tergite laterally red. Legs black; fore tibia often yellowish frontally; hind tibia sometimes dark reddish sub-basally. Pterostigma black.

♁. Body length 8.0-10.0 mm. Flagellum with 31-34 segments; 1 st flagellar segment 2.7× as long as wide. Tyloids on flagellar segments 6-15, long-oval, small, maximally 0.6× as long as their segments. OED 1.0× and OOD 1.3× ocellar diameter. MI 0.7. Fore metatarsus without apical tooth (fig. 96). Hind femur 3.8× as long as wide. 2 nd tergite 1.1× as wide as long; 2 nd to 4 th tergites with coarse dense punctures.

Color: black. Flagellum sometimes reddish apically. Palps mainly, mandible basally, usually clypeus laterally, facial orbit and spot on frontal orbit or inner orbit completely (fig. 75), stripe on outer orbit, ventral spot of scape, collar and upper margin of pronotum, spots on tegula and subtegular ridge, two posterolateral spots on scutellum (often confluent medially), apical bands or stripes on 6 th to 7 th tergites (sometimes apical band on 5 th tergite) ivory. 2 nd and 3 rd tergites completely and sometimes basal part of 4 th tergite red. Legs black; fore and mid femora, tibiae and tarsi ± yellowish frontally; hind tibia sometimes reddish-brown sub-basally. Pterostigma blackish.

Host: Satyrum pruni (Linnaeus, 1758) (Lep. Lycaenidae ) (ZSM).

S t u d i e d m a t e r i a l: from Austria, Bulgaria, Germany, Italy, Norway, Russia, Sweden, Turkey * (ZSM), Ukraine.