Alcochera truncata Sheng & Sun, 2021

Sun, Shu-Ping, Li, Tao, Zong, Shi-Xiang & Sheng, Mao-Ling, 2021, The genus Alcochera Förster (Hymenoptera, Ichneumonidae, Ctenopelmatinae) in China with a key to world species, Zootaxa 5023 (2), pp. 273-283 : 278-281

Alcochera truncata Sheng & Sun , sp. nov.

Figures 13–24

Material examined. Holotype, Female, CHINA: Hongyangu, 580m, Wugongshan Natural Reserve , Pingxiang , Jiangxi, 3 May 2016, Yü Yao ( IT).

Diagnosis. Subapical portion of clypeus ( Fig. 14 ) transversely convex, its apical margin truncate. Postocellar line 0.9 × as long as ocular-ocellar line. Areolet ( Fig. 19 ) triangular, receiving 2m-cu at its lower posterior corner. Lateromedian longitudinal and anterior transverse carinae of propodeum absent. First tergite ( Figs 21, 22 ) 1.5 × as long as posterior width, latero-median carina absent. Dorsal profile of ovipositor sheath ( Fig. 24 ), a little beyond middle, distinctly convex. Fore and mid coxae almost entirely black. Tergites 2–3 red.

Description. Holotype, female ( Fig. 13 ). Body length about 8.8 mm. Fore wing length 6.2 mm. Ovipositor sheath length 0.4 mm.

Head. Upper and lower portions of inner orbits slightly divergent, slightly emarginate opposite antennal socket. Face ( Fig. 14 ) 1.5 × as wide as long, almost flat; shagreened, with sparse indistinct punctures, upper margin with small median tubercle. Clypeus ( Fig. 14 ) 3.0 × as wide as long, almost smooth, basal portion with fine indistinct transverse wrinkles; subapical portion distinctly convex transversely; with yellowish brown setae; apical margin truncate. Mandible with dense brownish yellow setae; lower tooth distinctly longer than upper tooth. Malar space approximately 0.4 × as long as basal width of mandible. Gena ( Figs 15 , 16 ), vertex ( Fig. 16 ) and frons finely shagreened. Gena evenly convergent backward, with relatively dense yellowish brown setae. Postocellar line 0.9 × as long as ocular-ocellar line. Frons slightly concave. Antenna with 37 flagellomeres; ratio of length from first to fifth flagellomeres approximately: 2.3:1.2:1.1:1.1:1.0. Occipital carina complete, reaching hypostomal carina above base of mandible.

Mesosoma. Anterior margin of pronotum with fine indistinct longitudinal wrinkles; lateral concavity relatively narrow, upper portion with short transverse wrinkles; upper posterior portion shagreened, with indistinct fine punctures. Mesoscutum ( Fig. 17 ) shagreened, with fine punctures, distance between punctures 1.0–3.0 × diameter of puncture. Notauli slightly present on anterior portion of mesoscutum. Scutoscutellar groove smooth, shiny. Scutellum with texture as mesoscutum. Postscutellum distinctly convex, evenly concave anteriorly. Mesopleuron ( Fig. 18 ), metapleuron and propodeum ( Fig. 20 ) shagreened. Upper anterior portion of mesopleuron beneath subalar prominence with short indistinct transverse wrinkles. Epicnemial carina distant from anterior margin of mesopleuron, about 0.4 × as long as posterior margin of pronotum. Speculum absent. Episternal scrobe smooth, shiny. Metapleuron slightly evenly convex. Legs relatively stout; claw simple. Ratio of length of first to fifth hind tarsomeres: 4.9:2.4:1.7:1.0:1.6. Wings ( Fig. 13 ) yellowish brown, hyaline. Fore wing with 1cu-a distal to 1/M approximately by 0.3 × length of 1cu-a. Areolet ( Fig. 19 ) triangular, its stalk about 0.4 × as long as 2rs-m, joining 2m-cu at its lower posterior corner; 2-Cu 1.2 × as long as 2cu-a. Hind wing vein 1-cu approximately 2.3 × as long as cu-a. Propodeum ( Fig. 20 ) evenly convex, with dense brownish gray setae. Lateromedian longitudinal and anterior transverse carinae entirely absent. Posterior portion of lateral longitudinal carina and posterior transverse carina present. Area petiolaris almost smooth, shiny. Propodeal spiracle circular, connecting pleural carina by ridge.

Metasoma. First tergite ( Figs 21, 22 ) approximately 1.5 × as long as posterior width, evenly strongly widened posteriorly; latero-median carina absent; dorso-lateral and ventro-lateral carinae complete; spiracle small, circular, located approximately at anterior 0.4 of first tergite. Second tergite ( Figs 23 ) approximately 0.7 × as long as posterior width; anteromedian portion with short indistinct transverse wrinkles; posterior portion with fine indistinct punctures. Third tergite with texture as second tergite, about 0.7 × as long as posterior width. Fourth and subsequent tergites almost shiny, with dense short yellowish brown setae. Ovipositor sheath ( Fig. 24 ) approximately 3.9× as long as maximum width, dorsal profile beyond middle distinctly convex. Basal portion of ovipositor stout, apical portion beyond dorsal subapical notch ( Fig. 24 ) slender, dorsal subapical notch large, almost semicircular.

Coloration ( Fig. 13 ). Black, except for following: clypeus, mandible except basal end and teeth, maxillary palpi, labial palpi, parts of trochanters, basal portion of first tarsomere yellowish brown. Fore and mid femora yellowish red, tibiae brownish yellow. Hind femur except apical end, tergites 2–3 red. Basal portion of hind tibia yellowish red, basal end blackish. Posterior margin of first tergite reddish brown. Pterostigma brown. Veins darkish brown.

Male. Unknown.

Distribution. CHINA: Jiangxi.

Etymology. The specific name is derived from the apical margin of clypeus truncated.

Remarks. The new species is similar to A. aequalis Sheng, 1998 , but can be distinguished from the latter by the following combination of characters: Postocellar line 0.9 × as long as ocular-ocellar line; fore wing 2rs-m distinctly shorter than 3rs-m; face black; fore and mid coxae all most entirely black. A. aequalis: Postocellar line 0.6 × as long as ocular-ocellar line; fore wing 2rs-m as long as 3rs-m; face yellow; fore and mid coxae yellowish brown.

Figures

FIGURES 13–15. Alcochera truncata Sheng & Sun, sp. nov. Holotype. Female. 13 Habitus, lateral view 14 Head, anterior view 15 Head, lateral view.

FIGURES 16–19. Alcochera truncata Sheng & Sun, sp. nov. Holotype. Female. 16 Head, dorsal view 17 Mesoscutum, dorsal view 18 Mesosoma, lateral view 19 Areolet.

FIGURES 20–24. Alcochera truncata Sheng & Sun, sp. nov. Holotype. Female. 20 Postscutellum and propodeum, dorsal view 21 First tergite, dorsal view 22 First tergite, lateral view 23 Tergites 2 and 3, dorsal view 24 Apical portion of metasoma, lateral view.