Mesochorus heterodon, Horstmann, 2006

Riedel, Ravenhorst Matthias, 2018, Contribution to the Palaearctic species of Mesochorus G (Hymenoptera, Ichneumonidae, Mesochorinae): 1. The M. fulvus-group, Linzer biologische Beiträge 50 (1), pp. 687-716 : 696-697

Mesochorus heterodon HORSTMANN, 2006: 1467-1468 ( figs 29-32)

Holotypus: (♀) Italia Piemonte, La Cassa (Torino), VII.1982, Scaramozzino leg. (Munich), type studied.

Description: ♀: Bodylength 6-7 mm. Flagellawith 43-46 segments, very slender; 1 st flagellomeres length c.7-7.5x width and 0.8x eye length; 2 nd flagellomeres length 5x width; preapical flagellomeres c.1.8x longer than wide. Temples moderately narrowed behind eyes, length c.0.75x eye width. OOD 1.5-1.8. Face with slightly convergent sides, width 1.1x length of clypeus+face and 0.95x eye length. MI 0.5-0.6. Lower mandibular teeth more or less longer than the upper ones. Malar spaces and mandibular bases finely striate. Occipital carina complete medially. Genal carinae reach the hypostomal ones far from mandibular bases. Mesoscutum with dense coarse punctures; mesopleura with dense coarse punctures dorsally and moderately dense punctures ventrally; metapleura with dense but superficial punctures. Area basalis with apical stalk; area superomedia length c.2.1x width and 1.6x length of area petiolaris, costulae in frontal 0.3; area petiolaris length 0.7x width. Hind femora length 4.7x height; hind metatarsi long, length 0.51-0.56x length of hind tibiae; hind claws slender, with 2-3 short basal teeth; distal fore tarsomeres slightly swollen, length 2.3-2.8x width. Areolets pointed-sessile, very oblique; 2 nd recurrent veins distal to their middle; nervuli interstitial; postnervuli intercepted at basal 0.3-0.35; pterostigma length 3.3x width, radial veins in their distal 0.68. 1 st tergite length 3.3-3.5x width; postpetiole length smooth, 1.7x width; 2 nd tergite length 1.2x width. Ovipositor sheaths length 7.5-7.7x width and 0.7-0.73x length of hind metatarsi.

Colour: Reddish including ocellar space. Palps, mandibles except teeth, clypeus, genae, inner and outer orbits, hind edges of pronotum, tegulae, wing bases, fore and hind coxae and trochanters yellow. Pterostigmata very pale ochreous. Ovipositor sheaths dark brownish.

Males andhosts unknown.

Distribution: Bulgaria*, Germany, Italy, Norway*, Ukraine*.