Listrodromus nycthemerus (GRAVENHORST)

A. M, 2009, Illustrated key to the tribes of subfamilia Ichneumoninae and genera of the tribe Platylabini of world fauna (Hymenoptera, Ichneumonidae), Linzer biologische Beiträge 41 (2), pp. 1317-1608 : 1357-1359

Listrodromus nycthemerus (GRAVENHORST) (Plate 9)

Ichneumon nycthemerus GRAVENHORST 1820 - Mem. Acad. Sci. Torino 34: 320, ♀.

Listrodromus nycthemerus: WESMAEL 1844 - Nouveaux Mém. Acad. Roy. Let. Beaux-Arts

Belgique 18: 146, ♀. F e m a l e

F l a g e l l u m: Short, filiform, with 21 segments, without white annulus, rufous, not widened and only slightly flattened at the apical third; basal segments short, first segment 1,8 times longer than width at apex, segment 11 square from lateral. Flagellum 1,5 times shorter than the front wing and 1,8 times shorter than body length.

H e a d: Head contour from front rounded, very slightly transversal, 1,1 times wider than length; genae from front long, only two times shorter than height of an eye; eyes not great; temples from the front visible far than to middle of eyes; head from above stout, transverse, 1,7 times wider than length. Vertex from lateral straightly slanting down to occipital carina; temples behind eyes from above strongly swollen, rounded, long, 1,7 times longer than longitudinal diameter of eye at middle, from side parallel to hind margin of eye; occipital carina sharp all round, moderately high, occipital carina from above roundly concaved, far not reach level of eyes and hind ocelli, meeting with hypostomal carina on base of mandible; hypostomal carina not visible from lateral; malar space 1,5 times longer than the mandible base width; mandibles wide and massive, sharply curved from above behind base almost at right angle, not narrowed to apex, with two approxi- mately equal teeth separated by wide gape and situated in the same plane; clypeus flat, transverse, 1,5 times wider than length, confluent with face, of peculiar form, with thinned apex, apically with tooth and rather sharp lateral corners; clypeal foveae small, scarcely expressed; labrum not protrude from under clypeus; surface of face not differentiated; antennal cavities very slightly impressed not reach level of front ocellus and borders of eyes, laterally above antennal fossae with tubercles and with slight interantennal tubercle; margins of antennal fossae slightly elevated above face surface; ocelli moderately convex, of normal size, diameter of lateral ocellus 1,5 times less than distance from ocellus to eye; ocellar triangle slightly elevated. Front surface of head with the exception of apex of clypeus, densely punctured; other part of head smooth, shining, without microsculpture.

T h o r a x: Collar of pronotum moderately long, front border of pronotum straight from above; transverse furrow of pronotum deep, not interrupted by keel; pronotal base almost uniformly straight; pronotal ridge thickened, but not strongly. Mesonotum convex, of equal length and breadth; notauli developed in front third; axillary tongue not developed; surface of mesonotum with big superficial punctures, shining, without microsculpture; prepectus behind front coxae deeply impressed; prepectal carina sharp, at apex not reach front margin of mesopleurae; subalarum thick, high, not sharpened; speculum smooth, shining; area of mesopleural fovea very deeply and broadly impressed forms with mesopleural suture unit impression to hind margin of mesopleura; lower part of mesopleurae not separated angularly; sternauli very broad and deep, reach to middle of mesopleurae; lower part of mesopleurae roughly wrinkly-punctured, shining, without microsculpture; scutellum convex, from apex abrupt to scuto-scutellar groove and more gradually slanting to postscutellum, laterally carinated up to apex, its surface smooth, shining; postscutellum with two hollows and sharp longitudinal wrinkles on interspace. Hind margin of metanotum without projections opposite lateral longitudinal carinae. Propodeum from lateral strongly shortened, with sharp break; horizontal part 1,8 shorter than length of area posteromedia in middle; all carinae of propodeum developed, sharp and high; basal area short and deep; area superomedia hexagonal, 1,2 times shorter than breadth between costulae, costulae at middle of area superomedia; carina metapleuralis with sharp break at level of costulae; area dentipara at apex without tooth, only with broadened transversal carina; spiracles small, roundish. Surface of propodeum, except densely wrinkly-punctured metapleurae, roughly cellular-wrinkled.

L e g s: Quite strong; segments of tarsi of all legs distinctly thickened to apex; hind coxae without scopa; claws small, sharply curved at apex, pectinate, with 5 teeth.

W i n g s: Areolet big, pentagonal, symmetrical, with wide base; stigma dark and broad; radius short, straight, radial cell broad; nervulus antefurcal; ramulus slightly developed or not expressed; all veins of hind wing developed; membrane of wing hyaline, yellowish; veins dark. Front wing 1,2 times shorter than body length.

A b d o m e n: Amblypygous, shortly-oval; second tergite transversal, 1,5 times shorter than breadth at apex; tergites 2 and 3 divided by strong constriction. Petiolus slightly flattened at base, dorsomedian and dorsolateral carinae of petiolus meeting at its middle, ventrolateral carina slightly expressed; lateral surface of petiolus smooth; petiolus from lateral gradually transform to postpetiolus, first tergite almost straight as of Heresiarches , from above sharply broadened to postpetiolus; middle field only just marked and not carinated; spiracles small, circular, distance between them 3 times more than distance from spiracles to apex of tergite; surface of postpetiolus smooth, shining. Gastrocoeli sharply impressed, transverse, short, narrower than interval; interval longitudinallywrinkled; thyridia sharp, short, approached to base of second tergite; lunulae absent; lateral surface of second tergite vertical; surface of second tergite very densely punctured, shining, without microsculpture; base of third tergite longitudinally-wrinkled; third tergite with more delicate punctures, other tergites smooth, shining, polished. Hypopygium compressed from sides with oblong apex, but without fold. Sternites 2-4 strongly unsclerotized, with fold.

C o l o r a t i o n: Body black; white or yellow: face, except middle stripe, frontal orbits, external orbits broadly, pronotal ridge, subalarum, scutellum, postpetiolus, broad interrupted apical band on second tergite, band on third, apical spots on tergites 4-7; legs with exception of coxae and trochanters with yellow or light-brown pattern.

S i z e: Body length: 7,0; front wing: 5,7; flagellum: 3,8 mm.

M a l e

Flagellum of males with narrow tyloides on segments 5-14; claws smooth, gradually curved; coloration similar.