Mesochorus gibbosus 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 : 7

10. Mesochorus gibbosus SCHWENKE, 1999

Holotype: "() Oppach 2,2 km NNE 12.8.93, 294/93 H. Zoerner " [, no. 294/93, Germany: Saxony, 2.2 km NNE of Oppach, 12.8.1993, leg. K.H. Zoerner] ( SDEI?).

Some years ago, the female holotype had been studied by K. HORSTMANN (unpublished notes) but was actually not found in the material from SDEI, the ZSM or in the HORSTMANN collection. Since all paratypes are males, I was not able to study females of this taxon. Here, I give a translation of the short unpublished notes made by HORSTMANN :

As small as some specimens of Mesochorus dispar BRISCHKE but differs from M. dispar by: hind coxae black ventrally, face densely punctate, facial orbits only ventrally striate.

Ovipositor sheath stab-like, narrow, in the last quarter very slightly narrowed and bent towards dorsal, as long as hind metatarsi (but somewhat retracted). Hind claws without teeth.

Colour: Clypeus, mandible, malar space and gena yellow; face pale brownish; orbits partly yellow (indistinct); frontal orbit widely yellow-reddish; frons medially, ocellar field and vertex black; temple dorsal darkened (head somewhat darker than in dispar ). Mesosoma black; hind edge of pronotum yellow; propodeum black. 1 st tergite and 1 st sternite reddish in front of glymma (as in dispar ); 2 nd tergite black basally, apical 2/3 tongue-like yellow; 3 rd tergite yellow in the basal third; apical tergites with narrow yellow apical margins. Fore and middle legs yellowish-red; hind femora pale red; hind coxae blackish; hind tibiae ivory medially, basally not darkened, at apex with blackish ring (0.5x of tibial width); hind tarsomeres ivory, distally brownish, distal tarsomere brown. Pterostigma almost without pigmentation, slightly darker than wing, its margins somewhat darker.

Remark: This species seems to be correctly placed in the

key of the dispar -group ( SCHWENKE, 1999: 48–51).