Mesochorus gravis SCHWENKE, 1999

Riedel, Matthias, 2018, The types of Mesochorus GRAVENHORST (Hymenoptera, Ichneumonidae, Mesochorinae) described by W. SCHWENKE and deposited in the Senckenberg Deutsches Entomologisches Institut, Beiträge Zur Entomologie = Contributions to Entomology 68 (1), pp. 1-29 : 8

12. Mesochorus gravis SCHWENKE, 1999

( Figs 11a–d )

Holotype: "() Dessau 2.2 SO 5.8.1992 130/92 H. Zoerner " [, no. 130/92, Germany: Saxony-Anhalt, 2.2 km SE of the district Dessau of town Dessau-Rosslau, 5.8.1992, leg. K.H. Zoerner] ( SDEI).

Description: Missing: Both antennae. Body length 4.8 mm. Temple roundly narrowed behind eye, 0.55x as long as the eye width. OOD 1.2. Face coarsely and densely punctate, with parallel sides, about as wide as the length of clypeus+face and 0.87x as wide as the eye length. Malar space and ventral 0.3 of facial orbit striate. MI 0.25. Mandible with two equal teeth. Genal carina reaching the hypostomal carina far from mandibular base. Mesoscutum with rather dense coarse punctures; mesopleuron with dense coarse punctures dorsally and ventrally on frontal part with dense puncture getting scattered in caudal half; metapleuron with finer but dense punctures. Area basalis trapezoid, about as long as wide; area superomedia 2.2x longer than wide and about as long as the area petiolaris, costula in frontal 3/10 of length of area superomedia; area petiolaris 1.2x longer than wide. Hind femur 4.7x longer than wide; hind metatarsus 0.46x as long as the hind tibia; hind claws with three short but strong basal teeth. Areolet pointed, 2 nd recurrent vein slightly proximal to its middle; nervulus interstitial; pterostigma 3.4x longer than wide, radial vein in its distal 0.65, distal parts of radial veins slightly sinusoid. 1 st tergite 2.5x longer than wide; postpetiolus 1.3x longer than wide, with central rim; 2 nd tergite 0.95x as long as wide; thyridium transversal-oval. Stylet long, stab-shaped, not clubbed apically, 1.5x longer than the 2 nd hind tarsomere.

Colour: Black. Face and clypeus reddish and brownish; palps, mandible except teeth, gena, malar space and facial orbit cream-yellow. Frontal orbit with large ivory spots in ventral half; outer orbit reddish. Mesosoma reddish; hind edge of pronotum, tegula and wing base cream-yellow; mesoscutum with three brownish stripes; propodeum in basal 2/3 blackish, apically and metapleuron brownish. Metasoma black; 1 st tergite narrowly brownish at apex; 2 nd tergite yellowish in the apical 2.5/10 of tibial length; 3 rd tergite mainly yellowish, brown laterally and apically, following tergites blackish. Legs yellowish; hind coxa and hind femur reddish-yellow; hind tibia and hind metatarsus cream-yellow, only slightly and narrowly brownish at their apices. Pterostigma pale brownish, proximally and distally paler.

Remark: This taxon is correctly placed in the key for males ( SCHWENKE, 1999: 115–118) and is characterized by the long stylet and ivory spots on frontal orbit.

Figures

Fig. 11a-d: Holotype of Mesochorus gravis SCHWENKE: a. face; b. mesosoma; c. metasoma; d. stylet.