Orientochorus tonkinensis, Riedel, 2023

Riedel, Matthias, 2023, Contribution to the taxonomy of the Southeast Asian Mesochorinae (Hymenoptera, Ichneumonidae), Zootaxa 5245 (1), pp. 1-72 : 5-6

Orientochorus tonkinensis nov. sp.

( Figs 1A , 8A , 16A , 17A , 22A )

Holotype. (♀) NW Vietnam: Tonkin, Hoang Lien N. R. 10 km SW Sa Pa , c 1550 m, 22–29.x.1999, Malaise traps, C. v. Achterberg, RMNH´99 (Leiden).

Description. ♀: Body length 4.6 mm. Length of fore wing 4.4 mm.

Head. Flagellum very slender, with 29 flagellomeres; 1 st flagellomere 9.3 × longer than wide and 1.7 × longer than 2 nd flagellomere, 0.9 × as long as eye; 2 nd flagellomere 5.3 × longer than wide; preapical flagellomere 2.2 × longer than wide. Temple strongly and roundly narrowed behind eye, dorsally c 0.4 × as long as eye. OED 1.3 × and OOD 1.3 × ocellar diameter. Frons with microsculpture and fine superficial punctures, ± shining. Face ( Fig. 8A ) without subantennal transverse carina, granulate and finely and densely punctate, without central longitudinal ridge, width 1.1 × combined length of face and clypeus and 0.9 × eye length; inner eye margins slightly convergent ventrally. Clypeus slightly convex, c 1.5 wider than long, granulate and with sparse fine punctures; clypeal sulcus weakly present. Malar space 0.65 × as long as width of mandibular base, granulate and without groove between lower eye margin and clypeus. Mandible with two teeth, ventral tooth almost 2 × longer than dorsal tooth. Maxillary palp very long, c 1.3 × longer than eye. Occipital and genal carina complete, genal carina reaching hypostomal carina away from mandibular base, both carinae low.

Mesosoma . 1.7 × longer than high, covered with dense short grey setae. Side of pronotum punctate dorsally and granulate ventrally, with strong epomia. Notaulus slightly impressed at frontal margin of mesoscutum. Lateral lobe of mesoscutum densely punctate and shining, apical half of median lobe rugose-punctate. Scuto-scutellar groove smooth and finely punctate, transversely oval. Scutellum weakly convex, without lateral or apical carinae. Mesopleuron ( Fig. 16A ) with dense fine punctures fronto-dorsally and fine sparse setiferous punctures ventrally; speculum large, smooth. Metapleuron with fine dense punctures; juxtacoxal carina absent; submetapleural carina low. Area basalis rectangular, slightly longer than wide. Area superomedia ( Fig. 17A ) almost rectangular, 2.4 × longer than wide and 1.4 × longer than area petiolaris; anterior transverse carina (costula) absent.Area petiolaris 1.4 × wider than long. Hind femur 5.7 × longer than wide; hind metatarsus 0.6 × as long as hind tibia and 2.4 × longer than 2 nd hind tarsomere; hind claw with 3 small basal teeth. Areolet shortly sessile frontally; vein 2m-cu reaching its middle. Vein 1cu-a postfurcal by 1 × its width. Postnervulus intercepted in its middle. Vein RS slightly curved, not sinusoid. Pterostigma 3.3 × longer than wide. Hind wing with 4 distal hamuli.

Metasoma. 1 st tergite 2.6 × longer than wide, with distinct dorsal-lateral carina at level of spiracle. Postpetiolus finely rugose-punctate, with two partly developed paramedian longitudinal ridges. 2 nd tergite about as long as wide, finely granulate, with fine dense punctures in basal half. Thyridium transverse-oval. 3 rd and following tergites with fine superficial granulation, shining. Ovipositor sheath ( Fig. 22A ) densely pilose, slightly saber-shaped, 7.8 × longer than wide, 0.4 × as long as hind tibia and 0.8 × as long as hind metatarsus, moderately narrowed in apical 0.3.

Color. black. Flagellum brownish; scape and pedicel yellowish ventrally. Palps, fore and mid coxae and trochanters cream-yellow. Mandible except teeth yellowish. Malar space and apical 2/3 of clypeus red. Stripe on fronto-ventral margin and hind edge of pronotum, tegula, subtegular ridge, posterio-ventral spot of mesopleuron and upper mesepisternum reddish. 1 st and 2 nd tergites black, 2 nd tergite with yellow band in apical 0.2. Following tergites brownish. Ovipositor sheath black. Legs yellowish; hind tibia ochreous internally and brown externally; hind tarsus brown. Pterostigma brown.

♁ unknown.

Figures

FIGURE 1. Oriental Mesochorinae, habitus from lateral. A−Orientochorus tonkinensis n. sp. HT, B−Astiphromma bicoloratus n. sp. HT, C−Mesochorus achterbergi n. sp. HT, D−M. annamensis n. sp. HT, E−M. brevipunctatus n. sp. HT, F−M. cariniscuta n. sp. HT.

FIGURE 8. Oriental Mesochorinae, face from frontal. A−Orientochorus tonkinensis n. sp. holotype (HT), B−Astiphromma bicoloratus n. sp. HT, C−Mesochorus achterbergi n. sp. HT, D−M. annamensis n. sp. HT, E−M. brevipunctatus n. sp. HT, F−M. cariniscuta n. sp. HT, G−M. controversus n. sp. HT, H−M. diversidens n. sp. HT (♀).

FIGURE 16. Oriental Mesochorinae, mesopleuron from lateral. A−Orientochorus tonkinensis n. sp. HT, B−Mesochorus sulaensis n. sp. HT with juxtacoxal carina present, C−M. flavopronotalis n. sp. HT (♀), D−M. harlequinus n.sp. HT, E−M. malucutus n. sp. HT, F –M. pterostigmator n. sp. HT, G−M. tonkinesis n. sp. HT, H−M. vietnamensis n. sp. HT.

FIGURE 17. Oriental Mesochorinae, propodeum from dorsal. A−Orientochorus tonkinensis n. sp. HT, B−Astiphromma bicoloratus n. sp. HT, C−Mesochorus annamensis n. sp. HT, D−M. brevipunctatus n. sp. HT, E−M. cariniscuta n. sp. HT, F−M. diversidens n. sp. HT (♀), G−M. fuscomaculatus n. sp. HT, H−M. halmaherae n. sp. HT, I−M. harlequinus n.sp. HT.

FIGURE 22. Oriental Mesochorinae, ovipositor sheath from lateral. A−Orientochorus tonkinensis n. sp. holotype (HT), B−Mesochorus annamensis n. sp. HT, C−M. brevipunctatus n. sp. HT, D−M. cariniscuta n. sp. HT, E−M. controversus n. sp. HT, F−M. diversidens n. sp. HT, G−M. flavator n. sp. HT, H−M. flavopronotalis n. sp. HT, I−M. fuscomaculatus n. sp. HT, J−M. halmaherae n. sp. HT, K−M. harlequinus n.sp. HT, L−M. kinabaluensis n. sp. HT, M−M. lamdongensis n. sp. HT, N−M. longimurus n. sp. HT.