Indabracon nigricans sp. nov.

Figs 5, 6

Type material.

Holotype. ♀, China, Yunnan Prov., Xishuangbanna Yunjinghong, 650m, 23.VII.1957, Zang Lingchao, No. IOZ(E)1964520 (IZCAS). Paratype: 1♀, China, Yunnan Prov., Xishuangbanna Cheli-Damenglong, 600m, 29.IV.1957, Liu Dahua, No. IOZ(E)1964541 (IZCAS).

Diagnosis.

This new species is very similar to I. bicolor Yang & Chen, 2006, but can be separated from the latter by the following characters: scutellum black medially and remainder yellow, (entirely yellow in I. bicolor); apical third of pterostigma largely blackish (apical half of pterostigma dark brown and remainder yellow in I. bicolor); fore wing vein CU1b relatively short, 0.5 times as long as vein 3-CU1 (0.8 times in I. bicolor); T1 reddish yellow laterally (whitish yellow in I. bicolor) and medio-basal area of T2 rugose (smooth in I. bicolor).

Description.

Holotype, ♀, length of body 9.2 mm, of fore wing 8.7 mm, of ovipositor sheath 5.6 mm.

Head. Antenna incomplete, 49 segments remaining; third segment 1.2 and 1.3 times longer than fourth and fifth, respectively, the latter 1.1 times longer than wide; length of maxillary palp 0.9 times height of head; malar suture rather weak, sculptured, and with short setae (Fig. 6i); clypeus height: inter-tentorial distance: tentorio-ocular distance = 6: 10: 7; clypeus with dense, long setae; eye weakly emarginated (Fig. 6g); face punctate, especially laterally (Fig. 6g); eye height: shortest distance between eyes: head width = 14: 15: 30; frons largely smooth except for a few weak punctures, with some sparse short setae and a strong median groove (Fig. 6h); vertex largely smooth except for a few weak punctures, and with some sparse short setae; POL: OD: OOL = 4: 5: 12; length of malar space 1.4 times basal width of mandible; length of eye 2.0 times temple in dorsal view; temples largely glabrous except for a few long setae, and subparallel-sided behind eyes (Fig. 6h).

Mesosoma. Length of mesosoma 1.6 times its height (Fig. 6c); notauli impressed anteriorly half (Fig. 6d); mesoscutum largely smooth except for a few weak punctures, with sparse short setae (Fig. 6d); scutellar sulcus moderately narrow, deep, and with crenulae (Fig. 6d); scutellum distinctly convex, punctate especially posteriorly; metanotum strongly convex medially, and with a short median carina anteriorly (Fig. 6d); propodeum largely smooth except for a few weak punctures and some crenulae posteriorly, and with sparse setae medially, and dense, long setae laterally (Fig. 6d).

Wings. Fore wing (Fig. 6a): SR1: 3-SR: r = 23: 16: 3; 1-SR+M strongly bent after arising from 1-M, and 1.7 times longer than 1-M; 2-SR: 3-SR: r-m = 6: 16: 5; CU1b 0.5 times as long as 3-CU1; cu-a weakly postfurcal, and nearly not bent basally. Hind wing (Fig. 6b): 1r-m straight or nearly so; SC+R1: 2-SC+R: 1r-m = 14: 4: 9.

Legs. Length of fore femur: tibia: tarsus = 11: 13: 16; length of hind femur: tibia: basitarsus = 27: 42: 14; length of femur, tibia and basitarsus of hind leg 3.0, 6.0 and 3.5 times their maximum width, respectively.

Metasoma. Length of T1 0.9 times its apical width, median area convex and strongly coarsely rugose, medio-longitudinal carina only present posteriorly, lateral areas relatively narrow and smooth (Fig. 6j); lateral grooves of T1 distinctly crenulate (Fig. 6j); T2 coarsely sculptured including medio-basal area (Fig. 6e); antero-lateral grooves of T2 strongly developed and crenulate (Fig. 6e); second suture deep and crenulate, wide and curved medially, narrow laterally (Fig. 6e); T3-4 with antero-lateral grooves, and latero-posterior corner medium-sized; T3-5 coarsely sculptured, and with crenulate transverse subposterior groove (Fig. 6e); T6-7 largely rugose, and with dense long setae posteriorly; hypopygium acute apically, not reaching level of apex of metasoma; ovipositor sheath 0.6 times as long as fore wing.

Colour. Largely black (Fig. 5); head largely yellow, except for antenna (but scapus yellow ventrally), eyes, stemmaticum and apex of mandible black (Fig. 6g, h, k); prothorax, notaulic area, median mesoscutal lobe posteriorly, tegulae, and scutellum laterally yellow (Fig. 6c, d); fore (except for black claws) and middle legs (but coxa and claws black) yellow; T1 yellowish brown anteriorly and laterally, T6-7 pale yellow (Fig. 6e, j); wing membrane infuscate, and pterostigma (but blackish apically) yellow, veins dark brown (Fig. 6a, b).

Variation. Length of body of female 9.2-9.4 mm, of fore wing of female 8.4-8.7 mm, and of ovipositor sheath 5.6-6.2 mm; antenna with 51 segments; apical antennal segment acute, twice longer than wide; length of mesosoma 1.6-1.7 times its height; ovipositor sheath 0.6-0.7 times as long as fore wing.

Biology.

Unknown.

Distribution.

China (Yunnan).

Etymology.

Named after the blackish colour of the metasomal tergites: " Indabracon nigricans " is Latin for “blackish” .