Holotype, ♀ (ZUH), “S. China: Hunan, nr Zhangjiajie, Badagong Mts, Tian Ping Mt., 9–13.VII.2009, 550 m, Xi-Ying Li, RMNH’10”.

Dorsope present (Fig. 389); notauli complete (Fig. 386); medio-posterior depression of mesoscutum present (Fig. 386); hind tibia pale yellowish and with brown patch basally; 17^th-19^th (left) or 17^th-20^th (right) antennal segments of ♀ pale yellowish (Fig. 387); second metasomal tergite longitudinally costate (Fig. 389).

Holotype, ♀, length of body 2.2 mm, of fore wing 2.7 mm.

Head. Antenna with 26 segments and 1.3 times as long as fore wing; length of third segment 1.4 times fourth segment, length of third, fourth and penultimate segments 5.0, 3.6, and 3.2 times their width, respectively (Fig. 387); length of maxillary palp 1.4 times height of head; labial palp segments elongate (Fig. 384); occipital carina moderately close to hypostomal carina and dorsally absent; median groove behind stemmaticum present; hypostomal carina narrow; length of eye in dorsal view 4.4 times temple; frons with shallow median groove and pit, flattened and glabrous medially, smooth and laterally setose; face smooth, medially keel-shaped elevated (Fig. 388); width of clypeus 1.6 times its maximum height and 0.45 times width of face, clypeus convex, truncate ventrally, smooth and its ventral margin not differentiated and straight; hypoclypeal depression large (Fig. 388); malar suture absent; mandible normal, with medium-sized narrow ventral carina (Fig. 390).

Mesosoma. Length of mesosoma 1.4 times its height; dorsal pronope absent; pronotal side smooth, but medial groove with ventral oblique carina anteriorly and a short carina perpendicularly connected to it and posterior groove obsolescent (Fig. 384); epicnemial area smooth dorsally; precoxal sulcus only medially distinctly impressed, moderately widely rugose; rest of mesopleuron smooth (Fig. 384); pleural sulcus smooth; mesosternal sulcus strongly crenulate; notauli complete on disc, deep and moderately crenulate (Fig. 386); lateral mesoscutal lobes glabrous and middle lobe setose (Fig. 384); medio-posterior depression of mesoscutum small and part of notauli (Fig. 386); scutellar sulcus moderately crenulate; scutellum smooth and flat; dorsal surface of propodeum largely irregularly reticulate and with weak medio-longitudinal carina, posteriorly areolate (Fig. 386).

Wings. Fore wing (Fig. 385): pterostigma elliptical; 1-R1 reaching wing apex and 1.4 times as long as pterostigma; r:3-SR:SR1 = 2:25:60; 2-SR:3-SR:r-m = 16:25:8; r widened; 1-M straight; SR1 nearly straight; m-cu slightly postfurcal; cu-a slightly postfurcal and 1-CU1 slightly widened; first subdiscal cell closed, CU1b short; M+CU1 unsclerotized. Hind wing (Fig. 385): M+CU:1-M:1r-m = 4:3:2; cu-a straight; m-cu absent except for a faint trace.

Legs. Length of femur, tibia and basitarsus of hind leg 4.5, 10.2 and 6.3 times as long as wide, respectively; hind femur with long setae and of tibia moderately long (Fig. 393).

Metasoma. Length of first tergite 1.3 times its apical width, its surface evenly convex medially and with longitudinal (medially oblique) costae and dorsal carinae united in its anterior 0.5 and up to apex (Fig. 389); second tergite largely longitudinally finely costate (Fig. 389); third and following tergites smooth; length of setose part of ovipositor sheath 0.08 times fore wing and 0.25 times hind tibia (Fig. 392).

Colour. Black or blackish-brown; 17^th-19^th (left) or 17^th-20^th (right) antennal segments, palpi, tegulae and legs (but apical half of outer side of hind femur, base of hind tibia and hind tarsus more or less dark brown) pale yellowish; scapus, orbita, face laterally, clypeus, mandible, malar space and temple brownish-yellow; remainder of head dark brown; pterostigma and veins mainly brown; wing membrane slightly infuscate.

Molecular data. COI, 16S, 28S (CVA 4240).

*China (Hunan).

Unknown.

Name derived from “notauli” (Latin for “grooves of the notum”) and “fero” (suffix in Latin meaning “carrying or having”), because of the developed notauli.

The new species runs in the key by Chen and Weng (2005) to Opius mitis Chen & Weng, 2005 (= Xynobius wengi nom. n.). Xynobius notauliferus differs by having the notauli complete (posteriorly absent in Xynobius wengi), the lateral lobes of the meso-scutum are glabrous (largely setose), the length of eye in dorsal view 4.4 times temple (2.3 times) and the antenna with a pale yellowish ring (absent).