Chelonus (Microchelonus) recavus sp. nov.

Figs 65–68

Material examined. Holotype: 1 female, Xiangtou Mt., Guangdong Prov., China, 11.V.2004, Zaifu Xu, No. 20048105 (ZJUH) . Paratypes: 2 males, same label data as holotype but Nos. 20048092, 20048100 .

Diagnosis. This new species is similar to C. (M.) depressus (Thomson, 1874) sharing the medio-posterior depression of the metasomal carapace (Fig. 66D), but the two species can be separated by the following characters: antenna of female as long as head and 0.5 mesosoma combined (Fig. 66H) (versus slightly longer than head and mesosoma in C. (M.) depressus); maximum height of metasomal carapace posteriorly (Fig. 66D) (versus medially); 3 rd antennomere 2.2 × longer than wide (Fig. 66H) (versus 3.0 ×).

Description. Holotype, male, length of body 3.0 mm, of fore wing 1.6 mm.

Head. Head transverse, width of head 2.2 × its dorsal length, occiput slightly excavated; antennomeres 16, antenna slightly widened medially, length of 3 rd and penultimate antennomeres 2.2 × and 1.4 × their width, respectively (Fig. 66H); eye 1.3 × as long as temple in dorsal view; OOL: OD: POL= 15: 6: 11; temple parallel-sided behind eyes; vertex striate-rugulose; frons distinctly concave, smooth near antennal sockets (Fig. 66G); face flat, concentric punctate-rugose; clypeus densely punctulate and shiny, width of face 1.8 × its height; eyes slightly converging ventrally (Fig. 66F).

Mesosoma. Length of mesosoma 1.6 × its height; side of pronotum finely punctate, mesopleuron areolate-rugose (Fig. 66B); notauli indistinct, mesoscutum evenly convex, densely alveolate-rugose; scutellum rugulose, shiny; scutellar suture comparatively deep, narrow, with carinae; propodeum coarsely rugose, tubercles small and weak (Fig. 66C).

Wings. Vein r somewhat arched; marginal cell 0.5 × as long as pterostigma; pterostigma 2.8 × longer than wide; r: 3-SR: SR1=10: 11: 43; SR1 slightly curved outwards; marginal cell 1.8 × longer than submarginal cell; 1-CU1: 2-CU1=6: 18; 2-R1 absent (Fig. 66A).

Legs. Hind coxa mainly smooth and shallowly punctate with dense setosity; length of hind femur, tibia and basitarsus 3.1 ×, 4.3 × and 4.3 × their maximum width, respectively; length of inner hind tibial spur 0.5 × hind basitarsus.

Metasoma. Length of carapace 2.2 × its maximum width in dorsal view, widest at middle, apically narrowed; carapace longitudinally -rugose up to basal 70%, rugulose apically (Fig. 66E); carapace in lateral view 2.8 × longer than high, posterior height of metasoma 1.5 × its anterior height, medio-posteriorly with a depression in carapace in lateral view, apex of metasomal carapace slightly incurved (Fig. 66D).

Colour. Body black; antenna brown but scapus yellowish; palpi light yellow; pterostigma dark brown; middle of wing and its veins medium dark brown, wing base and its veins light brown; legs almost entirely dark brown, but hind tibia with a wide pale yellowish ring basally; carapace with yellowish irregular edge band in basal 1/3.

Male. Antennomeres 23, antenna filiform, not widened medially; occiput excavated (Fig. 68H); apex of metasomal carapace distinctly incurved (Fig. 68D); apical aperture in posterior view large, nearly round and median process of aperture with vertical carina (Fig. 68F); other characters as in female.

Biology. Unknown.

Distribution. China (Guangdong).

Etymology. Named after the medio-posterior depression of the carapace: “ recavus ” is Latin for arched inward, concave.