Stenaoplus baikalensis, Riedel, 2021

Riedel, Matthias, 2021, A New Contribution to the Knowledge of the East Palaearctic Ichneumoninae (Hymenoptera, Ichneumonidae), Linzer biologische Beiträge 53 (1), pp. 171-240 : 211-212

Stenaoplus baikalensis nov.sp. ( figs 94-97 )

H o l o t y p e: (♀) " Russia, E Siberia, lake Baikal near Anghasolka, 6.IV.2007, leg. Berlov; under bark of dead Pinus sylvestris " (coll. Riedel) .

D e s c r i p t i o n: ♀: Body length 10.2 mm. Flagellum slender and bristle-shaped, with 37 flagellomeres; 1 st flagellomere 3.2× longer than wide; widest flagellomere about square; preapical flagellomere 1.5× longer than wide. Temple strongly and almost linearly narrowed behind eyes. OED 1.0× and OOD 1.5× ocellar diameter. Frons densely punctate and granulate dorsally, dull. Face densely punctate and granulate. Clypeus flat, densely punctate, shining; apical margin sharp, slightly concave. MI 1.0. Mandible slender, lower tooth small, upper tooth covered by labrum. Gena densely punctate, laterally as wide as eye. Genal carina reaching hypostomal carina away from mandibular base; hypostomal carina low.

Collar without median longitudinal ridge; epomia present; side of pronotum punctate and granulate dorsally, finely rugose ventrally. Mesoscutum finely punctate and strongly granulate, dull. Notaulus impressed in frontal ¼ of mesoscutum. Metapleuron and metapleuron including speculum densely punctate; juxtacoxal carina present. Scutellum moderately elevated, slightly longer than wide, densely punctate and granulate, with complete lateral carina. Area basalis protruding forward medially, without distinct median tubercle. Area superomedia horseshoe-shaped, slightly longer than wide; anterior transverse carina absent. Posterior transverse carina low, without apophyses. Hind coxa finely and densely punctate, with grey scopa in apico-ventral third. Hind femur densely punctate, 3.9× longer than wide. Tarsi slender; 3 rd mid tarsomere 2.0× longer than wide. Claws not pectinate. Areolet pentagonal, frontal distance between veins 2rs-m and 3rs-m 2× their diameter; vein 2m-cu in its middle. Vein 1cu-a interstitial.

Metasoma strongly oxypygous. 2 nd to 5 th sternites with median folds. Postpetiolus moderately widened, without distinct dorsal carina, median and lateral fields not separated, with fine granulation medially and some coarse punctures laterally. 2 nd tergite 0.85× as long as wide. Gastrocoelus weakly impressed. Thyridium very large, slightly oblique, 2.5× wider than the interval. 2 nd and 3 rd tergites granulate and with dense superficial punctures, dull. Following tergites with very superficial punctures, ± shining. Ovipositor sheath reaching far behind metasomal apex (by length of 7 th tergite).

Color: black. Stripes on flagellomeres 8-12 ivory. Stripe on frontal orbit, short stripes on vertex and outer orbit, collar, hind edge of pronotum and apical spot on scutellum yellow. Legs including coxae and trochanters black; fore tibia with yellowish stripe frontally; hind femur narrowly reddish basally; hind tibia diffusely reddish-brown externally. Wings slightly infuscate; pterostigma dark brown.

♁ unknown.

R e m a r k: This new species differs from the known East Palaearctic Stenaoplus species by its reduced yellow color pattern on legs and metasoma. The collection date and location indicate an overwintering behavior of this species.

D i s t r i b u t i o n: Siberia.

Figures

Figs 94-97: Stenaoplus baikalensis nov.sp. ♀: (94) face from frontal, (95) head from dorsal, (96) propodeum from dorsal, (97) basal tergites from dorsal.