Mesoleptidea nigricoxalis Li & Sun, 2024

Li, Tao, Li, Bin & Sun, Shu-Ping, 2024, Three new species of Mesoleptidea Viereck (Hymenoptera, Ichneumonidae) from China, Zootaxa 5397 (2), pp. 251-263 : 256-259

Mesoleptidea nigricoxalis Li & Sun , sp. nov.

Figures 15–27

Material examined. Holotype, Female, CHINA: National Forest Park of Mt Wawu, Hongya , Sichuan Province, N 29°40´, E 102°58´; 1650 m, 13 July 2019; IT by Gui-Ru Kang, CBDPC.

Diagnosis. Clypeus with distinct punctures. Scutellum quadrate. Areolet forming an oblique triangle, receiving vein 2m-cu almost at its lower-posterior corner. Lateromedian longitudinal carinae of propodeum relatively distinct. Tergite 1 straight ( Fig. 25 ). Tergite 2 as long as posterior width. Tergite 3 shorter than its maximum width. Mesosoma and tergites 1–2 almost entirely black. Posterior part of ovipositor sheath narrowed posteriorly.

Description. Female ( Fig. 15 ). Body length about 10.9 mm. Fore wing about 8.4 mm. Ovipositor sheath about 0.5 mm.

Head. Face approximately 1.5 × as wide as long, shining with fine granular and dense setae, median portion slightly convex; sublateral portion longitudinal concave ( Fig. 16 ). Clypeus 2.7 × as wide as long, convex from basal to median portions, shining with sparse setae; subapical portion slightly concave, apical margin truncate ( Fig. 16 ). Mandible large and long, with dense setae basally; lower tooth as long as upper tooth ( Fig. 16 ). Malar space shiny, about 0.7 × as long as basal width of mandible ( Figs 16 , 18 ). Gena evenly convergent backward, with fine granular microsculpture and dense setae ( Fig. 18 ). Vertex with the same texture as gena ( Fig. 17 ). Postocellar line approximately 0.7 × as long as ocular-ocellar line. Frons slightly flat, with the same texture as vertex. Antenna with 39 flagellomeres; ratio of length from first to fifth flagellomeres: 2.2:1.2:1.1:1.0:1.0. Occipital carina complete, genal carina joining hypostomal carina above base of mandible.

Mesosoma. Pronotum shiny, dorsal half of concavity with oblique wrinkles and ventral half with irregular transverse wrinkles; dorsal margin with dense setae ( Fig. 19 ). Epomia absent. Mesoscutum convex, shiny, with dense setae; posteromedian part with dense granulate ( Fig. 20 ). Notaulus distinct on anterior portion of mesoscutum. Scuto-scutellar groove deep, shiny. Scutellum distinctly convex, shiny, with dense setae ( Fig. 20 ). Mesopleuron almost flat, lower portion with fine transverse wrinkles and dense setae ( Fig. 19 ). Speculum shiny. Dorsal end of epicnemial carina closing anterior margin of mesopleuron, almost reaching to subtegular ridge. Metapleuron slightly convex, shiny, with fine granular microsculpture, lower half relative shiny; submetapleural carina complete. Wings hyaline ( Fig. 21 ). Fore wing with vein 1cu-a distal to M&RS by 0.2 × length of 1cu-a. Areolet forming an oblique triangle, with short petiole, receiving vein 2m-cu almost at its lower-posterior corner. Postnervulus intercepted almost at middle. Hind wing vein 1-cu 4.0 × as long as cu-a. Ratio of length of hind tarsomeres from first to fifth: 4.8:2.6:1.7:1.0:1.3 ( Fig. 22 ). Propodeum convex, shiny, with dense long setae; basal median portion deeply semicircle concave; median portion with short transverse wrinkles; lateromedian longitudinal carinae relatively distinct; apico-median portion shiny, with longitudinal wrinkles. Propodeal spiracle small, circular, located at basal 0.2 of propodeum ( Fig. 23 ).

Metasoma. Tergite 1 approximately 6.1 × as long as anterior width, 3.0 × as long as posterior width ( Fig. 24 ); shiny, with fine reticulate texture and dense setae; latero-median carinae absent; dorso-lateral carinae interrupted after spiracle ( Fig. 25 ); ventro-lateral carinae complete; spiracle circular, located at middle of tergite. Tergite 2 approximately 1.4 × as long as anterior width, 0.9 × as long as posterior width; with fine granular microsculpture and dense setae; thyridium oblique elongate, concave ( Fig. 26 ). Tergite 3 approximately 0.8 × as long as anterior width; shiny, with evenly dense micro-setae ( Fig. 26 ). Ovipositor sheath 6.8 × as long as its width ( Fig. 27 ). Ovipositor strong, compressed, with subapical dorsal notch.

Coloration ( Fig. 15 ). Black, except the following: face except median longitudinal band dark reddish brown, clypeus, mandible except teeth dark reddish brown, malar space, lower portion of gena, maxillary and labial palpi, antenna except dorsal of scape and pedicel and basal half of flagellum dark brown to black brown, upper-posterior corners of pronotum, tegulae, fore and mid legs except basal margin of mid coxa black brown, hind leg except coxa and trochanter black brown and most femur dark reddish brown, ovipositor sheath brown to dark brown. Apical portion of third tergite, fourth and subsequent tergites dark reddish brown. Pterostigma except median portion brown and veins dark brown. Body with yellowish brown setae.

Male. Unknown.

Distribution. CHINA: Sichuan ( Fig. 42 ).

Etymology. The specific name is derived from the hind coxa being black.

Differential diagnosis. The new species is similar to M. nigra , but can be distinguished from the latter by the following combination of character states: lower portion of mesopleuron with dense setae and distinct transverse wrinkles ( Fig. 19 ); tergite 1 straight, 3.0 × as long as posterior width ( Figs 24, 25 ); tergite 3 shorter than its maximum width ( Fig. 26 ); and hind femur black. Mesoleptidea nigra : differs in having the lower portion of mesopleuron with fine indistinct and irregular wrinkles ( Fig. 5 ); tergite 1 uniformly arched, 3.7 × as long as posterior width ( Figs 11, 12 ); and tergite 3 longer than its maximum width ( Fig. 13 ); hind femur brown.

Figures

FIGURE 42. Distribution map of Mesoleptidea species of China (map from: http://bzdt.ch.mnr.gov.cn).

FIGURES 15–17. Mesoleptidea nigricoxalis Li & Sun, sp. nov., ♀, holotype (CBDPC). 15 Habitus, lateral view. 16 Head, anterior view. 17 Head dorsal view. Scale bars: 15 = 2.0 mm; 16 = 0.3 mm; 17 = 0.2 mm.

FIGURES 18–22. Mesoleptidea nigricoxalis Li & Sun, sp. nov., ♀, holotype (CBDPC). 18 Head, lateral view. 19 Mesosoma, lateral view. 20 Mesoscutum and scutellum, dorsal view. 21 Wings. 22 Hind tarsus. Scale bars: 18, 20 = 0.4 mm; 19, 22 = 0.5 mm; 21 = 1.0 mm.

FIGURES 23–27. Mesoleptidea nigricoxalis Li & Sun, sp. nov., ♀, holotype (CBDPC). 23 Propodeum. 24 Tergite 1, dorsal view. 25 Tergite 1, lateral view. 26 Tergites 2–3, dorsal view. 27 Apical portion of metasoma, lateral view. Scale bars: 23–25 = 0.3 mm; 26 = 0.5 mm; 27 = 0.2 mm.

FIGURES 4–9. Mesoleptidea nigra Li & Sun, sp. nov., ♀, holotype (CBDPC). 4 Head, lateral view. 5 Mesosoma, lateral view. 6 Mesoscutum and scutellum, dorsal view. 7 Fore wing. 8 Areolet. 9 Hind tarsus. Scale bars: 4–6= 0.3 mm; 7, 9 = 0.5 mm; 8 = 0.2 mm.

FIGURES 10–14. Mesoleptidea nigra Li & Sun, sp. nov., ♀, holotype (CBDPC). 10 Propodeum. 11 Tergite 1, dorsal view. 12 Tergite 1, lateral view. 13 Tergites 2–3, dorsal view. 14 Apical portion of metasoma, lateral view. Scale bars: 10–12, 14 = 0.3 mm; 13 = 0.5 mm.