Exetastes gracilicornis GRAVENHORST, 1829: 429

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 : 657-658

Exetastes gracilicornis GRAVENHORST, 1829: 429 (figs 12, 36, 76, 104, 122)

syn. nov. Exetastes ocellatus REY DEL CASTILLO, 1990: 241 , ♀ ♁, high-resolution photos of types studied.

D e s c r i p t i o n: ♀. Length 10-12 mm. Flagellum long and bristle-shaped, with 47- 60 flagellomeres; 1 st flagellomere 6.5-7.2× as long as wide and 0.7× as long as eye; preapical flagellomeres as long as wide. Temple moderately and roundly narrowed behind eye. OED 1.4-1.8× ocellar diameter. Inner eye margins parallel. Minimal facial width 0.8-0.9× eye length. Clypeus 1.9× as wide as long, with rather distinct basal transverse ridge. MI 0.4-0.5. Mandible short. Hypostomal carina low. Epomia weak. Mesoscutum very densely punctate, smooth and shining between punctures. Scutellum not carinate. Propodeum finely rugose; spiracle slit-shaped; apical transversal carina absent or weakly developed medially. Hind femur (4.4-) 4.8-5.9× as long as wide. Hind claws long, moderately bent apically, with short basal teeth. Areolet shortly sessile frontally, oblique; vein 2m-cu proximad its middle; ramellus short; vein 1cu-a slightly postfurcal or interstitial. Metasoma smooth and shining. 1 st tergite 1.4-1.5× as long as wide, with sparse setae laterally. 2 nd tergite 0.7-0.9× as long as wide. Ovipositor sheath 0.2-0.3× as long as hind tibia and 0.6-0.7× as long as 1 st tergite; ovipositor straight.

Color: black. Setae of mesosoma grey. Yellow coloration of mesosoma variable: stripes on flagellomeres 12/13-15/16, spot of subtegular ridge, sometimes collar, spot of tegula, anterolateral spot of mesoscutum, scutellum and posterolateral spot of propodeum ± yellow. Clypeus ± reddish, sometimes also base of mandible. 1 st tergite ±, 2 nd to 4 th tergites entirely and often 5 th tergite basally red (basal tergites sometimes with blackish suffusion); apical tergites often with narrow ivory hind margins. Sternites red, hypopygium black. Coxae black; rarely hind coxa reddish; trochanters often ± reddish. Legs otherwise mainly red; hind femur sometimes weakly infuscate apically; hind tibia usually brown in apical 0.3-0.5; hind tarsus brown or black, 2 nd to 4 th hind tarsomeres sometimes red or yellowish. Wings sometimes slightly infuscate; pterostigma ochreous.

♁. Length 9-11 mm. Flagellum with 43-51 flagellomeres; 1 st flagellomere 4.3-5.2× as long as wide and 0.7× as long as eye. OED 1.1-1.2× ocellar diameter. Clypeus 2× as wide as long. Apical transversal carina of propodeum often distinct medially. Hind femur 5.6-5.9× as long as wide. 1 st tergite 1.3-1.4× and 2 nd tergite 0.8× as long as wide.

Color: black. Flagellum black, often ± brownish. Base of mandible sometimes yellowish. Clypeus ochreous. Collar, anterolateral spot on mesoscutum, subtegular ridge, spot on tegula, scutellum, spot on posterolateral edge of area dentipara or subapical transversal band of propodeum ivory. 1 st tergite except black base, 2 nd to 4 th tergites entirely and 5 th tergite basally red. Legs except black coxae and trochanters mainly red; sometimes mid femur basally and hind femur entirely black; hind tibia yellow basally, ± infuscate apically; rarely fore and mid tibiae and tarsi yellowish externally; 2 nd to 3 rd /4 th hind tarsomeres ivory. Pterostigma ochreous.

Remarks: E. ocellatus REY DEL CASTILLO, 1990 was recently described from Spain and compared with E. segmentarius and E. robustus ( REY DEL CASTILLO 1990) but not with E. gracilicornis . E. ocellatus slightly differs from typical E. gracilicornis by stouter hind femur (4.4-5.0× in E. ocellatus ) and less extended red coloration of basal tergites. Since E. gracilicornis appears to be rather variable in the studied material, I synonymize both species here.

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