Apanteles (Choeras) brevinervus Song & Chen

Song, Sheng-Nan, He, Jun-Hua & Chen, Xue-Xin, 2014, The subgenus Choeras Mason, 1981 of genus Apanteles Foerster, 1862 (Hymenoptera, Braconidae, Microgastrinae) from China, with descriptions of eighteen new species, Zootaxa 3754 (5), pp. 501-554 : 506-509

Apanteles (Choeras) brevinervus Song & Chen , sp. n.

( Figure 2. a–j )

Description. Female. Length of body 2.8 mm, of fore wing 3.1 mm.

Head. 1.8 times as wide as long, almost equal to the width of mesoscutum. Antenna with 18 segments, segments finely setose and connected closely, almost as long as the body, subapical antennal segments moniliform and slightly elongated, length of 16th segment 0.9 times as long as 15th segment, length of third segment equal to fourth segment, length of third, fourth, 15th, 16th and penultimate segments 2.4, 2.3, 1.4, 1.2 and 1.1 times as long as their width, respectively. In dorsal view length of eye 1.4 times as long as temple. Ocellar triangle sparsely pubescent and shiny. Ocelli in a moderately low triangle, the posterior transverse tangent to the median ocellus slightly touching the posterior pair; ocelli small, their diameter almost equal the distance between the hind and fore ocellus. OOL: OD: POL= 11: 7: 18. Frons smooth and distinctly concave medially, narrowly punctulate and setose laterally and posteriorly. Vertex, temple densely and rather finely setose. Face and clypeus mat and distinctly punctate, densely and finely setose. Face with a distinct median longitudinal carina. Labrum flat, smooth, sparsely and finely setose. Length of malar space 0.7 times as long as basal width of mandible. Mandible relatively wide and big.

Mesosoma. Length of mesosoma 1.5 times as long as its height. Side of pronotum largely smooth, sparsely setose and rugose laterally, with distinctly ventral furrow and dorsal furrow which with a few longitudinal carinae. Propleuron smooth and strongly shiny. Prepectal carina completely absent. Precoxal sulcus shallow and smooth, longer than half of mesopleuron. Mesopleuron largely smooth and glabrous, but punctulate and setose anteriorly and ventrally. Mesoscutum finely and densely punctulate and setose, softly shiny. Notauli absent. Scutellum slightly convex, densely punctulate and setose, posteriorly with smooth and strongly shiny band, its width about 0.9 times as long as scutellum. Side of scutellum with wide crenulate depression, lunula large-sized and semicircular. Propodeum with a strong and regular median longitudinal carina which bifurcates into several short oblique carinae, more distinct at its base. Remaining part of propodeum slightly rugose, densely punctulate and setose.

Wings. Fore wing evenly covered with ivory hairs, denser towards the apex. Pterostigma relatively wide, 2.4 times as long as wide. Vein 1-R1 almost equal to the length of pterostigma and 2.2 times as long as the distance from it to the top of marginal cell. Vein r distinctly curved and 2 times as long as 2-SR, vein r arising beyond the middle of pterostigma and longer than breadth of pterostigma. Vein 2-SR straight. Stub of vein r-m of fore wing very short, resulting in an open second areolet, areolet absent. 1-CU1: 2-CU1= 1: 1. Vein 1-SR pointing to the junction of 1-CU1 and 2-CU1. Hind wing evenly covered with ivory setae. Vein cu-a curved. Edge of vannal lobe beyond its widest part concave and here without a fringe of hairs.

Legs. Hind coxa densely punctulate and pubescent, shiny. Length of hind coxa slightly shorter than half of mesosoma. Tarsal claws slender and setose. Longer spur of middle tibia not reaching apex of middle basitarsus. Length of femur, tibia and basitarsus of hind leg 3.5, 5.1 and 5.0 times as long as their width, respectively. Length of hind tibial spurs 0.4 and 0.3 times as long as hind basitarsus respectively. Hind femur densely punctulate and setose. Middle tibia has several rows of short bristles.

Metasoma. Tergite I almost quadrangular and strongly narrowed apically, its basal width 2.4 times as long as its apical width which is 1.3 times as long as median length of tergite II, lateral sides more or less straight but slightly concave apically, basally half with a relatively wide and shallow excavation; basal half smooth, the remainder half slightly rugose, sparsely punctulate and setose. Medial area of tergite II transverse and subtriangular, apical side strongly curved which is 2.1, 2.9 times as long as basal width and its length; mainly smooth but finely rugose medio-posteriorly, densely setose apically. Remaining tergites smooth and finely pubescent. Ovipositor sheath hairy and rather widened, lateral sides nearly parallel, length of it (total length) 1.4 times as long as hind tibia. Hypopygium largely sclerotized, membranous only near median line and tightly folded along the middle line, with longitudinal creases laterally and acute apically.

Colour. Head black. Mandible and clypeus black. Scape and pedicel black. Flagellum dark brown. Mesosoma mainly black. Wing membrane subhyaline and weakly brownish. Pterostigma and veins of wings weakly pigmented, except veins 1-R1 and C+SC+R yellowish. Coxa black brown. Trochanter brown. Fore femur brown basally half and the remainder yellowish brown. Fore tibia and tarsi yellow brown. Middle femur largely brown but the remainder yellowish brown. Middle tibia yellowish brown. Middle tarsi yellow. Hind femur dark yellowish brown. Hind tibia yellowish brown basally half and the remainder brown. Hind tarsi yellowish brown. Tibial spurs yellow. Tergites black. Ovipositor dark reddish brown, its sheath dark brown.

Variation. Body length 2.8–3.1 mm. Fore wing length 3.1–3.5 mm. Length of ovipositor sheath (total length) 1.3–2.0 times as long as hind tibia. Some individuals slightly different in colour pattern of wings.

Male. Unknown.

Biology. According to labels, hosts are Euzophera batangensis Caradja (Pyralididae) , Retinia cristata (Walsingham) (Olethreutidae) , and a larva of Geometridae .

Material examined. Holotype, ♀, China, Zhejiang Prov., Gaozhou, 1984.VII–VIII, Yan Zhiwei, No. 845914 ( ZJUH). Paratypes (all in ZJUH): 1♀, China, Zhejiang Prov., Suichang, 1977. VIII, Host: Euzophera batangensis Caradja, Chen Hanlin, No. 772260; 1♀, China, Zhejiang Prov., Lishui, 1981. IX. 28, Zhu Kunyan, No. 815592; 1♀, China, Zhejiang Prov., Hangzhou, 1981. III. 7–8, Ma Yun, No. 810529; 1♀, China, Zhejiang Prov., Raoping, 1987. VIII, Host: Retinia cristata (Walsingham) , Chen Zefan, No. 896625; 1♀, China, Gansu Prov., Tianzhu, 1989. VI.23, Host: a larva of Geometridae, Yu Jihe, No. 911046; 1♀, China, Xinjiang Prov., Wulumuqi, 1991. VII. 23, He Junhua, No. 914858.

Distribution. China (Zhejiang, Gansu, Xinjiang) ( Fig. 20 ).

Remark. The new species is similar to Apanteles (Choeras) avus (Tobias et Kotenko, 1984) , but can be distinguished by the vein 1-R1 almost equal to the length of pterostigma (the latter longer); the length of ovipositor sheath (total length) 1.3–2.0 times as long as hind tibia (the latter noticeably shorter); and vein r curved and distinctly longer than 2-SR (the latter straight and almost equal).

Etymology. The specific name “ brevinervus ” derives from the Latin prefixion “brevi-” and noun “nervus”, referring to the very short vein 1-R1 of fore wing.

Figures

FIGURE 20. Distribution map of Choeras species in China I. ●: Apanteles (Choeras) angustus Song & Chen, sp. n.; ■: Apanteles (Choeras) brevinervus Song & Chen, sp. n.; ▲: Apanteles (Choeras) compressifemur (Chen & Song, 2004); Δ: Apanteles (Choeras) curvinervus Song & Chen, sp. n..

FIGURE 2. a – j. Apanteles (Choeras) brevinervus Song & Chen, sp. n. a, habitus, lateral view; b, antenna; c, hind wing; d, fore wing; e, head, dorsal view; f, head, frontal view; g, T 1 – T 3, dorsal view; h, mesosoma, dorsal view; i, mesosoma, lateral view; j, metasoma, lateral view.