Stenobarichneumon nigritor, Riedel & Watanabe, 2025

Stenobarichneumon nigritor sp. nov.

( Figs 44–47 View FIGURES 44–47 )

Holotype. ( ♀) [ Japan] Kagoshima Pref., Yakushima Isl., Arakawa, Malaise trap (Y1), 1200 m alt., 29. VII. – 25. VIII. 2007, T. Yamuchi et al. leg. ( Kanagawa).

Etymology. The species name refers to the largely black coloration of the body.

Description. Female. Body length 6.5 mm. Fore wing 4.9 mm.

Head. Flagellum with 29 flagellomeres, filiform; 1 st flagellomere 2.0× as long as wide, 7 th flagellomere square, widest flagellomere 1.3× as wide as long. Head 2.1× as wide as long. Temple rather short, moderately and roundly narrowed behind eye. OED 1.1× ocellar diameter. Temple with sparse punctures, strongly shining. Frons and face densely punctate, shining. Clypeus slightly convex, with sparse punctures in apical half; apical margin sharp and slightly concave. Mandible with two teeth; ventral tooth much smaller than dorsal tooth, not bent inwards. MI 0.7. Gena with sparse punctures. Genal carina reaching hypostomal carina far from mandibular base, hypostomal carina slightly wider than genal carina.

Mesosoma . Notaulus impressed in frontal 0.2 of mesoscutum. Mesoscutum densely punctate, shining. Mesopleuron densely punctate, partly rugose-punctate posteriorly; speculum partly smooth. Metapleuron densely punctate; juxtacoxal carina present. Scutellum moderately and roundly elevated, wider than long, with sparse punctures and lateral carina in basal 0.2. Propodeum completely carinate, without apophysis; spiracle slit-shaped. Area basalis trapezoid, with median tubercle. Area superomedia heart-shaped, about as long as wide, almost smooth centrally; costula reaching its middle. Hind coxa densely punctate, without scopa. Hind femur densely punctate, 2.8× as long as wide. External surface of hind tibia without denticular spines. Claws simple. Areolet pentagonal, frontal distance between veins 2rs-m and 3rs-m 2.0× their width; vein 2m-cu reaching its middle. Vein 1cu-a postfurcal by 1.0× its width.

Metasoma. Oxypyygous. Postpetiole moderately widened and densely punctate, without latero-median carina, median field not separated. Gastrocoelus impressed, granulate. Thyridium large, slightly oblique, 1.2× as wide as interval between thyridia. 2 nd tergite 1.2× as wide as long. 2 nd and 3 rd tergites densely punctate, shining. Ovipositor sheath reaching beyond metasomal apex by half length of 7 th tergite.

Color . Black. Flagellomeres 8–12 ivory dorsally. Palps yellowish. 2 nd and 3 rd tergite with narrow ivory apical margins; 6 th tergite with apical ivory band and 7 th tergite with dorsal ivory spot. Legs black; fore femur apically and fore tibia frontally ochreous; hind femur narrowly red basally. Wings almost hyaline; pterostigma brown.

Male unknown.

Distribution. Japan (Yakushima Isl.).

Remark. This new species differs from the Stenobarichneumon basiglyptus (Kriechbaumer, 1890) which have been reported from the Kuriles ( Uchida,1936) by its mainly black basal tergites.