Mesochorus pelvís, Schwenke, 2002

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 : 699-700

Mesochorus pelvís SCHWENKE, 2002: 91 ( figs 39-45 )

syn. Mesochorus hamatus SCHWENKE, 1999: 71, preoccupied by TOWNES, 1945.

Ho l o t y p u s: (♂) I, TNRiva Rocchetta, 400-800m, 20.5.1982, Haeselb. (Munich), type studied. syn. Mesochorus falcatus SCHWENKE, 1999: 71, preoccupied by DASCH, 1974, synonymized by HORSTMANN, 2006: 1477.

Holotypus: (♂) Dessau 4 km SSW, 7.8.86, K.H. ZOERNER; 100/86 Taubeufer (Müncheberg), type studied.

syn. Mesochorus lunatus SCHWENKE, 2002: 91 (nom. nov. for M. falcatus SCHWENKE), synonymized by HORSTMANN, 2006: 1477.

syn. nov. Mesochorus pectinellus HORSTMANN, 2006: 1476-1477.

Ho l o t y p u s: (♀) 38, ex Puppenvon Cymatophoridae (Munich) , type studied.

Ta xonomica l r emark: This taxon shows some sexual dimorphism in the size of ocelli and the forms of claws. Due to other structural similarities, especially the bare proximal half of the subbasal cells of fore wings, Ihave no doubt about the above mentioned synonymy of M. pectinellus .

Description: ♀: Bodylength 7-9 mm. Flagellawith 35-42 segments; 1 st flagellomeres length c.6.0-6.2x width and 0.55x eye length; 2 nd flagellomeres length 3.5- 4x width; preapical flagellomeres c.2x longer than wide. Temples strongly narrowed behind eyes, length 0.45-0.5x eye width. Ocelli large, OOD 0.5-0.6. Face with slightly convergent sides, width 1.0-1.1x length of clypeus+face and 0.7x eye length. MI 0.25. Mandibles with two equal teeth, rarely upper mandibular teeth slightly larger than lower ones. Malar spaces, ventral 0.3 of facial orbits and often bases of mandibles finely striate. Occipital carina complete medially. Genal carinae reach the hypostomal carinae near of mandibular bases (distance c.0.5x malar length). Mesoscutum with fine dense punctures; mesopleura with fine dense punctures dorsally and fine scattered punctures ventrally; metapleura with fine scattered and superficial punctures. Area basalis usually narrowly trapezoid or triangular, length c.1.5x width; area superomedia length 1.5x width and c.1.0x length of area petiolaris, costulae in frontal 0.35; area petiolaris length 1.0-1.1x width. Hind femora length 4.6x height; hind claws with 5 very long teeth, strongly bent apically; distal fore tarsomeres swollen, length 2.2-2.4x width. Areolets pointed-sessile, slightly oblique; 2 nd recurrent veins in or proximal to their middle; nervuli interstitial or more or less postfurcal; postnervuli intercepted in their basal 0.2- 0.25; pterostigma length 3.6x width, radial veins in their distal 0.6; subbasal cells of fore wings completely bare in the proximal half. 1 st tergite length 2.6-2.7x width; postpetiole length 1.4-1.5x width; 2 nd tergite length 1.1x width. Ovipositor sheaths length 4.2x height and 0.7-0.75x length of hind metatarsi.

Colour: Pale reddish-brown (including flagella and ovipositor sheaths). Palps, mandibles except teeth, genae, facial orbits, hind edges of pronotum, tegulae and wing bases yellow. Ocellar space brownish, sometimes pale. Pterostigmata pale ochreous, their margins darker.

♂: Bodylength 6-7.5 mm. Flagellawith 35-40 flagellomeres. OOD 0.7-0.85. Temples roundly narrowed behind eyes, length 0.6-0.65 eye width. Mesopleura with fine scattered punctures ventrally. Hind femora length 5.3-5.6x height; hind claws with two basal teeth, strongly falcate apically. Subbasal cells of fore wings completely bare in the basal half. Claspers slender, apically blunt, not clubbed, length 17x width and 1.25-1.4x length of 2 nd hind tarsomeres. Colour as described for the ♀.

Hosts: Cymatophora sp. (Lep. Drepanidae ) via Rogas sp. (Hym. Braconidae ).

Distribution: Bulgaria*, France*, Germany, Italy, Japan*, Russia* (St. Petersburg district and Far East), Sweden*, United Kingdom*.

Figures

Figs 39-45: Mesochorus pelvis SCHWENKE ♀: (39) face, (40) wing base, (41) distal fore tarsomere, (42) hind claw (♂), (43) hind claw, (44) ovipositor sheaths, (45) head.