Megastylus (Megastylus) yindianense Sheng & Li, 2022

Zhang, Shu-Jie, Zhou, Qing, Li, Tao & Sheng, Mao-Ling, 2022, The genus Megastylus Schiødte (Hymenoptera, Ichneumonidae, Orthocentrinae) in China with a key to the species of China and Oriental Region, Zootaxa 5091 (3), pp. 455-466 : 463-465

Megastylus (Megastylus) yindianense Sheng & Li , sp. nov.

Figures 21–30

Material examined. Holotype, Female, CHINA: Dezhai Forest Farm, Yindian , Minquan , Henan, 22 October 2020, Mao-Ling Sheng . Paratype: 1 female, same data as holotype .

Diagnosis. Propodeum without wrinkles, with deep smooth anteromedian concavity. Fore wing vein 2m-cu strongly inclivous. Basal portion of first tarsomere ( Fig. 27 ) strongly curved concave, inner profile with dense fine setae, spur reach to middle of concavity. Tergite 1 mat, with dense indistinct punctures. Mesopleuron, mesosternum, hind coxa and femur and tibia except subbase and apex slightly black, reddish brown.

Description. Female ( Fig. 21 ). Body length 3.4–4.0 mm. Fore wing length 3.2–3.5 mm. Ovipositor sheath length approximately 0.25 mm.

Head. Face ( Fig. 22 ) 1.4 × as wide as long, slightly convex, with sparse brown setae; almost parallel laterally, smooth, shiny; upper margin with small indistinct median tubercle. Clypeal sulcus distinct. Anterior tentorial pit relatively small, upper margin distinctly below a line connecting lower margins of eyes. Clypeus strongly convex, texture as face, 1.7 × as wide as long, median portion of apical margin weakly arched forwardly. Mandible with two sharp teeth. Malar space 1.4 × as long as basal width of mandible. Subocular sulcus distinctly exist. Gena and vertex ( Figs 3, 4 ) shiny, posterior portion converging to occipital carina. Postocellar line 1.1 × as long as ocular- ocellar line. Antenna with 35–37 flagellomeres; flagellomeres with relatively longer setae. Ratio of length from first to fifth flagellomeres: 11.5:4.7:4.3:3.8:3.4. Occipital carina complete, joining hypostomal carina far above base of mandible.

Mesosoma. Pronotum ( Figs 23 , 25 ) shiny, anterolateral portion slightly shagreened. Epomia indistinct. Mesoscutum ( Fig. 24 ) strongly convex, shiny, slightly shagreened; notauli weakly vestigial at anterior end. Scutoscutellar groove smooth, shiny. Scutellum ( Fig. 9 ) convex, with texture as mesoscutum, lateral carina almost reaching posterior end. Postscutellum small, smooth. Mesopleuron ( Fig. 25 ) finely shagreened; lower portion weakly convex, indistinctly finely punctate; upper end of epicnemial carina distance from front edge of mesopleuron, and 0.6 height to subtegular ridge. Metapleuron evenly convex, with dense fine punctures, distance between punctures 0.2–0.8 × diameter of puncture. Fore femur compressed; basal portion of first tarsomere ( Fig. 27 ) strongly curved, inside with dense fine setae. Hind femur 6.7 × as long as its maximum width. Hind tibia 9.7 × as long as its maximum width; inner profile of apical end with dense distinct fine setae; longer spur 0.3 × as long as first tarsomere. Hind tarsus as long as hind tibia. Ratio of length of hind tarsomeres from first to fifth: 20.0:9.5:6.6:4.5:8.3. Claw small, simple. Wings ( Fig. 28 ) slightly brownish, hyaline. Fore wing with vein 1cu-a interstitial. Areolet absent. Vein 2m-cu with two bullae. Postnervulus intercepted slightly below middle. Posterior half of hind wing vein M+CU distinctly arched, 1-cu 2.3 × as long as cu-a, discoidella unpigmented. Without prepropodeum. Propodeum ( Fig. 26 ) evenly convex, with dense indistinct punctures, posterior transverse carina closing posterior end of propodeum; anteromedian portion with deep transverse smooth concavity, which approximately 0.2 × as long as propodeum; lateromedian and lateral longitudinal carinae absent; apicomedian portion shiny. Propodeal spiracle small, circular.

Metasoma. Tergite 1 ( Fig. 29 ) with texture as propodeum; shagreened. 3.1 × as long as apical width, posterior half beyond spiracle slightly widened; latero-median and dorso-lateral carinae absent; ventro-lateral carina complete. spiracle slightly elliptic, located at anterior 0.4 of tergite 1. Tergite 2 strongly widened posteriorly; same longth as posterior width, 0.8 × as long as tergite 1; with almost similar texture to tergite 1. Thyridium elliptic, closed to anterior margin of tergite 2. Third and subsequent tergites shiny, with indistinct fine punctures. Fourth Posterior and subsequent tergites compressed. Ovipositor sheath ( Fig. 30 ) 0.6 as long as apical depth of metasoma.

Coloration ( Fig. 21 ). Black, except for following: Scape, pedicel and basal portion of flagellomeres blackish brown. Setae of flagellomeres almost black. Face black, obscurely slightly reddish. Maxillary palpi and labial palpi yellow. Clypeus, propleuron, lower portion of pronotum, mesopleuron except upper anterior portion darkish brown, mesosternum, hind coxa, hind femur except apex, hind tibia except subbase and apex slightly black, reddish brown. Fore and mid legs and hind trochanter yellowish brown. Hind tarsus brownish black. posterior margin of tergite 2, anterior half of tergite 3 and posterior margin yellowish white. Pterostigma and veins brownish black.

Distribution. CHINA: Henan.

Etymology. The specific name is derived from the type locality.

Remarks. The new species is similar to M. (M.) cruentator Schiødte, 1838 and M. (M.) orbitator Schiødte, 1838 , but can be distinguished from the latters by the following combination of characters: Propodeum with deep anteromedian transverse concavity; basal portion of first tarsomere ( Fig. 27 ) strongly curved, inner profile with dense fine setae; mesoscutum, scutellum and propodeum entirely black. M. (M.) cruentator and M. (M.) orbitator : Propodeum without anteromedian concavity; basal portion of first tarsomere ( Fig. 27 ) not curved, inner profile without dense fine setae; mesoscutum, scutellum and propodeum at least partly brown or red brown.

Figures

FIGURES 21–24. Megastylus (Megastylus) yindianense Sheng & Li, sp. nov. Holotype. Female. 21 Habitus, lateral view 22 Head, anterior view 23 Head and pronotum, lateral view 24 Head and mesoscutum, dorsal view.

FIGURES 25–30. Megastylus (Megastylus) yindianense Sheng & Li, sp. nov. Holotype. Female. 25 Mesosoma, lateral view 26 Propodeum. 27 Front tibia and basal portion of tarsus, lateral view 28 Fore wing 29 Tergites 1–2, lateral view 30 Apical portion of metasoma, lateral view

FIGURES 1–4. Megastylus (Dicolus) mentouense Sheng & Li, sp. nov. Holotype. Male. 1 Habitus, lateral view 2 Head, anterior view 3 Head, dorsal view 4 Head and pronotum, lateral view.

FIGURES 5–9. Megastylus (Dicolus) mentouense Sheng & Li, sp. nov. Holotype. Male. 5 Mesoscutum and scutellum, dorsal view 6 Mesosoma, lateral view 7 Postscutellum, Prepropodeum and propodeum 8 Tergite 1, dorsal view 9 Tergites 2–3, dorsal view