Apanteles (Choeras) angustus 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 : 504-506

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

( Figure 1. a–j )

Description. Female. Length of body 3.2 mm, of fore wing 3.2 mm.

Head. 2.0 times as wide as long, slightly longer than the width of mesoscutum. Antenna with 18 segments, with dense and short setae, almost as long as the body, subapical antennal segments much 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 4.0, 3.7, 1.8, 1.9 and 2.1 times as long as their width, respectively. In dorsal view length of eye 1.8 times as long as temple. Ocellar triangle finely setose. Ocelli in a moderately high triangle, the posterior transverse tangent to the median ocellus hardly touching the posterior pair; ocelli large, their diameter longer than the distance between the hind and fore ocellus. OOL: OD: POL= 17: 6: 10. Frons distinctly concave and smooth medially, narrowly punctulate, setose and strigose laterally and posteriorly. Temple, vertex, face and clypeus finely and densely setose, strongly punctate and softly shiny. Face with an indistinctly median longitudinal carina. Length of malar space 0.6 times as long as basal width of mandible.

Mesosoma. Length of mesosoma 1.6 times as long as its height. Side of pronotum smooth and strongly shiny, with narrow ventral furrow and dorsal furrow which with a few longitudinal carinae. Propleuron smooth and strongly shiny. Prepectal carina completely absent. Precoxal sulcus deep, smooth, shiny and about half length of mesopleuron. Mesopleuron largely and distinctly punctulate and setose, but smooth and glabrous medially and medio-dorsally. Mesoscutum densely punctulate and setose, indistinct posteriorly and softly shiny. Notauli absent. Scutellar sulcus narrow with a few longitudinal carinae, width about 0.8 times as long as scutellum. Scutellum slightly convex medially, relatively sparsely punctulate and setose, softly shiny. Side of scutellum with rather narrow crenulate depression, lunula large-sized and semicircular. Propodeum with slightly rugose median band, anteriorly distinctly punctulate and sparsely setose, postero-laterally strongly rugose and remainder area smooth, no areola, costulae or median carina.

Wings. Fore wing evenly covered with brown and fine hairs, denser towards the apex. Pterostigma relatively narrow, 3.3 times as long as wide. Vein 1-R1 1.6 times as long as pterostigma and 7.4 times as long as the distance from it to the top of marginal cell. Vein r 1.2 times as long as 2-SR and slightly curved, r arising slightly beyond the middle of pterostigma and slightly 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= 7: 9. Vein 1-SR pointing to 2- CU1. Hind wing evenly covered with brown setae. Vein cu-a slightly curved. Edge of vannal lobe beyond its widest part very slightly concave and here without a fringe of hairs.

Legs. Hind coxa densely punctulate and setose, shorter than half of thorax. Tarsal claws setose. Longer spur of middle tibia not reaching apex of middle basitarsus. Length of femur, tibia and basitarsus of hind leg 3.0, 4.9 and 4.5 times as long as their width, respectively. Length of hind tibial spurs 0.4 and 0.2 times as long as hind basitarsus respectively. Hind femur rather densely setose and punctulate.

Metasoma. Tergite I very long and distinctly quadrangular, narrower apically, its basal width 1.8 times as long as its apical width which is 0.7 times as long as median length of tergite II, lateral sides more or less straight basally and slightly concave apically, basal 0.3 with a relatively wide and shallow excavation; smooth and shiny, rather sparsely setose medio-laterally. Tergite II quadrangular and apical side more or less straight, apical width 1.9 and 2.1 times as long as basal width and its length; strongly smooth and shiny which has a row of hairs on the posterior margin. Remaining tergites smooth, shiny and sparsely setose apically respectively. Ovipositor sheath very narrow and finely hairy, very slender at the base and apex, sided nearly parallel medially, length of it (total length) 1.6 times as long as hind tibia. Hypopygium largely sclerotized, membranous only near the median line and folded along the middle line apically, acute apically and without longitudinal creases laterally.

Colour. Head black. Labrum and mandibles dark brown. Clypeus black. Scape largely yellow and small area of apical brown. Pedicel and flagellum dark brown. Mesosoma black. Wing membrane subhyaline and weakly infuscate. Pterostigma and veins of wings dark brown, except veins M+CU and cu-a of hind wing weakly pigmented. Fore and middle legs yellow except distal tarsi black and fore coxa pale yellow. Hind coxa dark yellowish brown ventrally and apically, but darkened dorsally and laterally. Remainder of hind leg yellowish brown. Tibial spurs pale yellow. Tergite I blackish brown. Remaining tergites brown but yellowish-brown laterally. Ovipositor yellowish brown, its sheath dark brown.

Variation. Body length 2.6–3.5mm. Fore wing length 2.6–3.6mm. Propodeum unstably and slightly rugose. Tergite II sometimes subtriangular. Length of ovipositor sheath (total length) 1.2–1.6 times as long as hind tibia. And some individuals slightly different in colour pattern.

Male. Unknown.

Biology. Unknown.

Material examined. Holotype, ♀, China, Hainan Prov., Jianfengling, 2007. VI. 5–7, Xiao Bin, No. 200606880 ( ZJUH). Paratypes (all in ZJUH): 1♀, China, Zhejiang Prov., Moganshan, 1982. VI. 12, Chen Xuexin, No. 922759; 1♀, China, Fujian Prov., Mt. Meihua, Guihe-Youpoji, 1998. VII. 22, FanJinjiang, No. 886275; 1♀, China, Hunan Prov., Shimen, Hupingshan, Sanhecun, 2009. VII. 1, Tang Pu, No. 200901229; 1♀, China, Hainan Prov., Jianfengling Tianchi, 2007. X. 22–23, Liu Jingxian, No. 200710671.

Distribution. China (Zhejiang, Fujian, Hunan, Hainan) ( Fig. 20 ).

Remark. The new species is similar to Apanteles (Choeras) batrachedrae (Kotenko, 1992) , but can be distinguished by the head width slightly wider than the width of mesoscutum (the latter narrower); the subapical antennal segments elongated, almost 2 times as long as wide (the latter slightly elongated, almost cubic); and the vein 1-R1 about 7.4 times as long as the distance from it to the top of marginal cell (the latter about 4.0–5.0 times).

Etymology. The specific name “ angustus ” derives from the Latin adjective “angust”, referring to the very narrow mesosoma and metasoma.

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