Barichneumon THOMSON

Riedel, Matthias, 2024, The genus Virgichneumon HEINRICH in the West Palaearctic region (Hymenoptera, Ichneumonidae, Ichneumoninae), Linzer biologische Beiträge 56 (1), pp. 149-199 : 150-151

Key of the genera related to Barichneumon THOMSON

(modified after RASNITSYN & SIYTAN 1981 and TERESHKIN 2005)

1 Flagellum of ♀ strongly lanceolate, widest flagellar segment usually more than 2× as wide as long. Genal carina usually reaching hypostomal carina at or close to mandibular base. Sometimes body large (> 13 mm) and basal tergites with ivory spots. Thyridium in both sexes poorly developed or absent, Gastrocoelus slightly impressed........ ................................................................................................. Melanichneumon THOMSON

- Flagellum of ♀ filiform, bristle-shaped or slightly lanceolate, widest flagellar segment less than 2× as wide as long. If genal carina reaching hypostomal carina at mandibular base, then body smaller (usually less than 13 mm) and basal tergites without ivory color pattern. Gastrocoelus and thyridium variously developed..........................................2

2 Thyridium of ♁ separated from the base of 2 nd tergite by more than its width, closer to base than its width in ♀. Subtegular ridge ± slender and sharp, black, rarely with small ivory marks. Flagellum of ♀ filiform, and of ♁ often with ivory ring. Head black, vertex and facial orbit rarely with ivory spots, clypeus black. Frons usually densely and coarsely rugose-punctate. 6 th and 7 th tergites (in ♁ sometimes 7 th tergite and paramere) with ivory spots. Lateral lobe of mesoscutum usually densely punctate. .............................. ..................................................................................................... Vulgichneumon HEINRICH

- Thyridium in both sexes closer to the base of 2 nd tergite than their width; if widely separated, then subtegular ridge thick and ivory AND/OR head including frontal orbit and vertex with extended ivory coloration. If subtegular ridge (rarely) sharp, then lateral lobe of mesoscutum and often frons with sparse punctures. Flagellum of ♀ bristle-shaped or slightly lanceolate, in ♁ usually without ivory ring. Metasomal apex in ♁ often (rarely in ♀) without ivory spots. .......................................................................3

3 1 st flagellar segment at least 1.5×, often more than 2× as long as wide. In ♁, 6 th flagellar segment distinctly longer than wide. In ♀, face with clypeus rather narrow, at most 2× as wide as long (usually narrower), in ♁ usually longer than wide. Gastrocoelus ± distinctly impressed and with longitudinal ridges. Body length sometimes more than 12 mm, flagellum with more than 26 segments. ................................. ..................................................................................................... Virgichneumon HEINRICH

- 1 st flagellar segment in ♀ usually not more than 1.5× as long as wide. In ♁, 6 th flagellar segment transverse or square. Face with clypeus in ♀ more than 2× as wide as long, usually with protruding median field, in ♁ transverse. Gastrocoelus often not or weakly impressed and ± smooth. Body length not more than 12 mm, usually much smaller. Flagellum sometimes with fewer segments. .................................. Barichneumon THOMSON