Exetastes bilineatus GRAVENHORST, 1829

Riedel, Matthias, 2023, The genus Exetastes GRAVENHORST in the West Palaearctic region, with description of a new species (Hymenoptera, Ichneumonidae, Banchinae), Linzer biologische Beiträge 55 (2), pp. 641-692 : 651-652

Exetastes bilineatus GRAVENHORST, 1829

D e s c r i p t i o n: ♀. Length 12-13 mm. Flagellum long and bristle-shaped, with 60- 64 flagellomeres; 1 st flagellomere 5.8× as long as wide and 0.6× as long as eye; preapical flagellomeres longer than wide. Temple strongly and almost linearly narrowed behind eye. OED 1.6× ocellar diameter. Inner eye margins slightly convergent ventrally. Minimal facial width 0.8-0.9× eye length. Clypeus 2.0× as wide as long. Mandible not elongate. MI 0.5. Mesoscutum densely rugose-punctate. Scutellum not carinate. Propodeum rugose-punctate; spiracle oval-shaped; apical transversal carina indistinct. Hind femur 6.7-7.5× as long as wide. Hind claws long, distinctly bent apically, without or with basal teeth. Areolet pointed frontally, oblique, vein 2m-cu reaching its middle; vein 1cu-a slightly postfurcal. Metasoma finely granulate, dull. 1 st tergite 2.0× as long as wide, with very sparse punctures. 2 nd tergite about as long as wide. Ovipositor sheath 0.3-0.4× as long as hind tibia and 0.7-0.8× as long as 1 st tergite; ovipositor straight.

Color: black. Setae of mesosoma pale. Stripes of flagellomeres 11-16, collar, hind edge of pronotum, sometimes anterolateral spot on mesoscutum, apical spot of scutellum and usually 3 rd and 4 th hind tarsomeres ± ivory. Apical margin of 1 st tergite, 2 nd to 4 th tergites entirely and 5 th tergite ± (sometimes also 6 th tergite basally) red. Coxae, trochanters and trochantelli black; fore and mid legs otherwise mainly reddish, femora ± infuscate; hind leg black; hind tibia basally ± reddish-brown. Pterostigma dark brown.

♁. Length 12 mm. Flagellum with 59 flagellomeres. OED 1.5× ocellar diameter. Hind femur 6.5× as long as wide. 1 st tergite 2.1× as long as wide, ± dull, with sparse punctures laterally. 2 nd tergite 0.9-1.0× as long as wide.

Color: black. Stripes of flagellomeres 13-17, collar, hind edge of pronotum, anterolateral spot on mesoscutum, spots on tegula and subtegular ridge, apical spot of scutellum and usually 3 rd and 4 th hind tarsomeres ivory. Apical margin of 1 st tergite, 2 nd to 5 th tergites entirely and 6 th tergite basally red. Coxae, trochanters and trochantelli black; fore and mid legs otherwise mainly reddish, femora ± infuscate; hind leg black; hind tibia basally ± reddish-brown. Pterostigma dark brown.

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