Blacus (Blacus) xizangensis sp. nov.

(Figs 29–30)

Material examined. Holotype: ♀, China, Xizang, Bomi, Moge, alt. 3772m, 11.VI.2009, Tan Jiangli, No. 200906263 (ZJUH).

Description. Female. Length of body 3.5 mm, length of fore wing 3.2 mm.

Head. Antennomeres 17, slender (Fig. 30C); length of first flagellomere 1.3 × length of second flagellomere; length of first, second and penultimate flagellomere 3.4, 2.6 and 1.3 × their width, respectively; length of maxillary palp 0.6 × height of head; occipital carina complete; frontal suture present; OOL: OD: POL = 24: 9: 14; length of eye in dorsal view 1.0 × length of temple; face superficially rugose; malar suture absent, length of malar space 0.7 × basal width of mandible.

Mesosoma. Length of mesosoma 1.6 × its height; side of pronotum largely reticulate-rugose; precoxal sulcus complete, wide and reticulate-rugose (Fig. 30E); notauli complete, moderately wide and rugose (Fig. 30D); mesoscutal lobes densely setose; scutellum largely smooth, its lateral carina complete, not protruding apically; propodeal tubercles small; surface of propodeum reticulate-rugose, medial area absent (Fig. 30F).

Wings. Fore wing: parastigma distinctly differentiated from vein C+SC+R, first discal cell widely truncate anteriorly; vein 3-SR+SR1 of fore wing nearly straight; vein CUla of fore wing distinctly bent basally, distinctly below level of vein 2-CU1; 1-CU1: 2-CU1 = 5: 14; 2-M present (Fig. 30I).

Legs. Hind coxa with a rugose carina; length of femur, tibia and basitarsus of hind leg 5.25, 9.8 and 7.1 × their width, respectively.

Metasoma. Length of first tergite 1.7 × its apical width, somewhat widened apically, nearly parallel-sided, reticulate-rugose (Fig. 30G); remainder tergites smooth (Fig. 30G); length of ovipositor sheath 0.50 × length of fore wing, 1.0 × length of hind femur, 0.7 × length of hind tibia.

Colour. Black; mandible yellowish-brown; palpi and all legs yellow; metasoma (but first tergite black), tegulae, pterostigma, parastigma, veins, ovipositor and sheath brown; wing membrane infuscated.

Male. Unknown.

Biology. Unknown.

Distribution. China (Xizang).

Etymology. The specific name xizangensis refers to the collection site of holotype, Xizang autonomous region.

Notes. The new species is similar to B. (B.) radialis Haeselbarth, 1973 because antenna is more slender basally than apically, hind femur less robust, parastigma distinctly differentiated from vein C+SC+R, first discal cell widely truncate anteriorly, vein CUla of fore wing distinctly bent basally, distinctly below level of vein 2-CU1, vein 2-M of fore wing present, first metasomal tergite somewhat widened apically, nearly parallel-sided, and frontal suture present, but differs by having unicolorous antenna (bicoloured in B. (B.) radialis), antenna more slender apically (less slender), length of ovipositor sheath 0.50 × length of fore wing (approx. 0.26 ×), and somewhat longer than hind femur (1.0 ×).