Blacus ( Blacus ) tianmushanensis, Lu & Chai & Achterberg & Tang & Chen, 2024

Blacus ( Blacus) tianmushanensis sp. nov.

( Figs 27–28 View FIGURE 27 View FIGURE 28 )

Material examined. Holotype: ♀, China, Zhejiang, Tianmu Mtn, Chanyuan Temple , 16.V.1988, Lou Xiaoming, No. 883235 ( ZJUH) . Paratype: 1♀, China, Guizhou, Kuankuoshui Reserve , 2–3. VI .2010, Tang Pu, No. 201003140 ( ZJUH) .

Description. Female. Length of body 2.7 mm, length of fore wing 2.3 mm.

Head. Antennomeres 17, slender ( Fig. 28C View FIGURE 28 ); length of first flagellomere 1.4 × length of second flagellomere; length of first, second and penultimate flagellomere 4.75, 3.5 and 1.8 × their width, respectively; maxillary palp 0.9 × height of head; occipital carina complete; frontal suture distinctly present; OOL: OD: POL = 24: 7: 12; length of eye in dorsal view 0.9 × length of temple; face distinctly rugose ( Fig. 28B View FIGURE 28 ); malar suture absent, length of malar space 2.4 × basal width of mandible.

Mesosoma. Length of mesosoma 1.6 × its height; side of pronotum largely reticulate-rugose ( Fig. 28E View FIGURE 28 ); precoxal sulcus complete, wide and reticulate-rugose ( Fig. 28E View FIGURE 28 ); notauli complete, wide and distinctly crenulate ( Fig. 28D View FIGURE 28 ); mesoscutal middle lobe sparsely pubescence, lateral lobes glabrous; scutellum rugose, its lateral carina complete, not protruding apically; propodeal tubercles absent; surface of propodeum reticulate-rugose, medial area present ( Fig. 28G View FIGURE 28 ).

Wings. Fore wing: parastigma distinctly differentiated from vein C+SC+R, first discal cell nearly acute anteriorly; vein 3-SR+SR1 of fore wing straight; vein CUla of fore wing distinctly bent basally, distinctly below level of vein 2-CU1; 1-CU1: 2-CU1 = 1: 4; 2-M present and long ( Fig. 28H View FIGURE 28 ).

Legs. Hind coxa with a carina dorsally; length of femur, tibia and basitarsus of hind leg 5.5, 10.0 and 9.4 × their width, respectively.

Metasoma. Length of first tergite 2.1 × its apical width, nearly parallel-sided, reticulate-rugose ( Fig. 28G View FIGURE 28 ); remainder of tergites partly distinctly rugose ( Fig. 28G View FIGURE 28 ); length of ovipositor sheath 2.4 × length of fore wing, 7.9 × length of hind femur, 5.45 × length of hind tibia ( Fig. 28I View FIGURE 28 ).

Colour. Brown; half basal of antenna, mandible, palpi, tegulae, all legs and ovipositor yellow; first metasomal tergite yellowish-brown; wing membrane infuscated.

Variation. First discal cell of fore wing acute to narrowly truncate anteriorly; 1-CU1: 2-CU1 = 1: 4 to 1: 6; length of first metasomal tergite 1.9–2.1 × its apical width; hind femur, tibia and tarsus yellow to brown.

Male. Unknown.

Biology. Unknown.

Distribution. China ( Zhejiang, Guizhou).

Etymology. The specific name tianmushanensis refers to the collection site of holotype, Tianmu Mtn.

Notes. The new species is similar to B. ( B.) longicaudatus Tobias, 1976 because notauli are wide and distinctly crenulate, ovipositor sheath very long, parastigma distinctly differentiated from vein C+SC+R, vein CUla of fore wing distinctly bent basally, distinctly below level of vein, first metasomal tergite nearly parallel-sided, and vein 3-SR+SR1 of fore wing straight, but differs by having scutellum rugose (mainly smooth in B. ( B.) longicaudatus ), vein 2-M of fore wing comparatively long (comparatively short), medial area of propodeum present (absent), scutellar sulcus with about 4 carinae (about 7 carinae), antenna comparatively slender apically (less slender), length of ovipositor sheath 2.4 × length of fore wing (0.97 ×), and face distinctly rugose (superficially rugose).

This new species is also similar to B. ( B.) rugifacialis sp. nov., but differs by having the body brown (black in B. ( B.) rugifacialis ), length of malar space 2.4 × basal width of mandible (2.0 ×), metasomal tergites partly distinctly rugose (slightly punctate), length of first metasomal tergite 1.9–2.1 × its apical width (1.7 ×), length of ovipositor sheath 2.4 × length of fore wing (1.5 ×) and approx. twice as long as body (approx. as long as body).