Mesochorus (Stictopisthus) kinabaluensis, Riedel, 2023

Riedel, Matthias, 2023, Contribution to the taxonomy of the Southeast Asian Mesochorinae (Hymenoptera, Ichneumonidae), Zootaxa 5245 (1), pp. 1-72 : 17-18

Mesochorus (Stictopisthus) kinabaluensis nov. sp.

( Figs 3B , 9H , 14D , 18A, 22L)

Holotype. (♀) [green] Kinabalu Park, 6°5´N 116°33´E, Sorinsim, SW III 40 years; [white] SW III, B 5 , F 1 , 7.3.1997 A. Floren ( ZSM).

Description. ♀: Body length 4.8 mm. Fore wing 3.8 mm.

Head. Flagellum with 36 flagellomeres; 1 st flagellomere 7.0 × longer than wide and 1.8 × longer than 2 nd flagellomere, 0.7 × as long as eye; 2 nd flagellomere 4.3 × longer than wide; preapical flagellomere 2.9 × longer than wide. Occipital carina complete medially. Temple strongly and roundly narrowed behind eye, dorsally 0.3 × as long as eye. OED 1.5 × and OOD 0.8 × ocellar diameter. Frons smooth, with fine transverse aciculation laterally. Face ( Fig. 9H ) densely punctate, without median ridge, width 1.0 × combined length of face and clypeus and 1.0 × eye length; inner eye margins parallel. Subantennal transverse carina not dipped medially. Malar space and narrow facial orbit striate. Malar space 1.1 × as long as width of mandibular base. Mandible with two equal teeth. Genal carina reaching hypostomal carina away from mandibular base, both carinae low.

Mesosoma . 1.7 × longer than high. Side of pronotum smooth. Mesoscutum with dense punctures, shining. Scuto-scutellar groove ( Fig. 14D ) with c 12 longitudinal ridges. Scutellum rounded in profile, with rather dense punctures. Mesopleuron densely punctate fronto-dorsally, with rather dense to dense punctures ventrally. Dorsal end of epicnemial carina reaching frontal margin of mesopleuron. Metapleuron with rather dense punctures. Submetapleural carina low. Propodeum ( Fig. 18A ) completely carinate. Area basalis almost rectangular, slightly longer than wide. Area superomedia 1.9 × longer than wide and 1.0 × as long as area petiolaris, smooth; anterior transverse carina (costula) reaching at 4/10 of its length. Area petiolaris as long as wide. Hind femur 4.3 × longer than wide; hind metatarsus 0.6 × as long as hind tibia and 3.0 × longer than 2 nd hind tarsomere; hind claw with two small basal teeth. Areolet shortly sessile frontally; vein 2m-cu in its middle. Vein 1cu-a postfurcal by 0.6× its length. Postnervulus intercepted basad its middle. Hind wing with 4 distal hamuli. Nervellus of hind wing vertical.

Metasoma. 1 st tergite 2.8 × longer than wide. Postpetiolus longitudinally striate. 2 nd tergite 1.3 × wider than long. Thyridium comma-shaped. Ovipositor sheath ( Fig. 22L ) with sparse setae, 8.3 × longer than wide, 0.6 × as long as hind tibia and 1.0 × as long as hind metatarsus, continuously and strongly narrowed towards apex.

Color. Head reddish-yellow. Palps, mandible except teeth, malar space, scape and pedicel yellow. Flagellum brownish, basal flagellomere ochreous. Mesosoma yellowish; pronotum, tegula, mesopleuron and metapleuron pale yellow. 1 st tergite reddish-brown, basally yellowish, with reddish apical spot. 2 nd tergite yellow, with large brown V-shaped spot in basal half. 3 rd tergite brown, with yellow band in basal 0.2. 4 th and 5 th tergites brown, narrowly yellow laterally; following tergites yellow. Ovipositor sheath pale brownish. Fore and mid coxae and all trochanters cream-yellow; legs otherwise yellow; hind tibia basally and in apical 0.2 brownish. Pterostigma ochreous-hyaline.

♁ unknown.

Taxonomical remark. This new species belongs to the subgenus Stictopisthus and is characterized by brownish 3 rd to 5 th tergites and the strongly narrowed ovipositor sheath which is almost pointed apically.

Figures

FIGURE 3. Oriental Mesochorinae, habitus from lateral.A−Mesochorus harlequinus n. sp. HT, B−M. kinabaluensis n. sp. HT, C−M. lamdongensis n. sp., D−M. longimurus n. sp. HT, E−M. longistylus n. sp. HT, F−M. longivalvator n. sp. HT.

FIGURE 9. Oriental Mesochorinae, face from frontal. A− Mesochorus diversidens n. sp. paratype (PT) (♁), B−M. flavator n. sp. HT, C−M. flavopronotalis n. sp. HT (♀), D−M. flavopronotalis n. sp. PT (♁), E−M. fuscomaculatus n. sp. HT, F−M. halmaherae n. sp. HT, G−M. harlequinus n.sp. HT, H−M. kinabaluensis n. sp. HT.

FIGURE 14. Oriental Mesochorinae, mesoscutum from dorsal.A−Mesochorus achterbergi n. sp. HT (♁), B−M. carinisctua n. sp. HT with carinate scutellum, C−M. flavopronotalis n. sp. HT, D−M. kinabaluensis n. sp. HT, E−M. sabahensis n. sp., F−M. malucutus n. sp. HT.

FIGURE 18. Oriental Mesochorinae, propodeum from dorsal. A− Mesochorus kinabaluensis n. sp. HT, B−M. longimurus n. sp. HT, C−M. longistylus n. sp. HT, D−M. malaysiacus n. sp. HT, E−M. malucutus n. sp. HT, F−M. nigripleuris n. sp., G−M. nigromaculatus n. sp. HT, H−M. pictiloides n. sp. HT, I−M. pterostigmator n. sp.

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.