Blacus (Blacus) adustiabdominus sp. nov.

(Figs 1–2)

Material examined. Holotype: ♀, China, Fujian, Wuyi Mtn, Xingcun Town, 20.IV.2009, Tan Jiangli, No. 201605131 (ZJUH) . Paratypes: 3♀♀, China, Guangdong, Shixing, Chebaling, 19.IV.2002, Xu Zaifu, Nos. 20050568, 20051005; 21.VIII.2003, Xu Zaifu, No. 20052130 (ZJUH) .

Description. Female. Length of body 1.9 mm, length of fore wing 2.0 mm.

Head. Antennomeres 17, slender (Fig. 2C); length of first flagellomere 1.1 × length of second flagellomere; length of first, second and penultimate flagellomere 4.8, 4.0 and 1.6 × their width, respectively; maxillary palp 1.1 × height of head; occipital carina complete (Fig. 2A); frontal suture present; OOL: OD: POL = 7: 2: 5; length of eye in dorsal view 0.9 × length of temple; face smooth (Fig. 2B); malar suture absent, length of malar space 1.75 × basal width of mandible.

Mesosoma. Length of mesosoma 1.5 × its height; side of pronotum rugose ventrally, smooth dorsally (Fig. 2D); precoxal sulcus complete, wide and reticulate-rugose (Fig. 2D); notauli complete and narrow, nearly smooth (Fig. 2E); mesoscutal lobes glabrous (Fig. 2E); scutellum largely smooth, its lateral carina complete, not protruding apically; propodeal tubercles absent; surface of propodeum reticulate-rugose, medial area absent (Fig. 2F).

Wings. Fore wing: parastigma slightly differentiated from vein C+SC+R, first discal cell acute anteriorly; vein 3-SR+SR1 of fore wing nearly straight; vein CUla of fore wing nearly at same level as vein 2-CU1; 1-CU1: 2-CU1 = 1: 4; vein 2-M absent (Fig. 2I).

Legs. Hind coxa slightly rugose; hind femur swollen apically, length of femur, tibia and basitarsus of hind leg 4.6, 12.5 and 9.5 × their width, respectively.

Metasoma. Length of first tergite 1.7 × its apical width, widened apically, reticulate-rugose (Fig. 2G); remainder of tergites smooth (Fig. 2G); length of ovipositor sheath 0.21 × length of fore wing, 1.1 × length of hind femur, 0.7 × length of hind tibia.

Colour. Dark reddish-brown; base of antenna, clypeus, mandible, palpi, tegulae, pterostigma, parastigma, veins and all legs yellow; side of pronotum, metasoma (except first tergite), ovipositor and sheath brown; wing membrane infuscated.

Variation. Length of first metasomal tergite 1.7–1.8 × its apical width; length of fore wing 1.9–2.0 mm; length of ovipositor sheath 0.21–0.22 × length of fore wing; side of pronotum yellowish-brown to brown.

Male. Unknown.

Biology. Unknown.

Distribution. China (Fujian, Guangdong).

Etymology. The specific name adustiabdominus refers to the brown metasoma and is derived from “ adustus ” (Latin for brown) and “ abdomen ” (Latin for abdomen).

Notes. The new species is similar to B. (B.) inopinus van Achterberg, 1976 because parastigma is small and narrow, slightly differentiated from vein C+SC+R, first discal cell of fore wing acute anteriorly, scutellum largely smooth, ovipositor sheath somewhat longer than hind femur, vein CUla of fore wing nearly at same level as vein 2-CU1, vein 2-M of fore wing absent, propodeal tubercle absent, length of first metasomal tergite 1.7 × its apical width, and malar space longer than basal width of mandible, but differs by having narrow and nearly smooth notauli (wide and distinctly crenulate in B. (B.) inopinus), posterior surface of propodeum less reticulate (more reticulate), antenna equally wide overall (narrowed medially and widened apically), length of malar space 1.75 × basal width of mandible (1.2 ×), and length of ovipositor sheath 0.21–0.22 × length of fore wing (0.27 ×).