Stantonia vietnamica van Achterberg

Achterberg, Cornelis van, Long, Khuat Dang & Chen, Xue-xin, 2017, Review of Stantonia Ashmead (Hymenoptera, Braconidae, Orgilinae) from Vietnam, China, Japan, and Russia, with descriptions of six new species, ZooKeys 723, pp. 61-119 : 101-104

Stantonia vietnamica van Achterberg sp. n. Figs 112, 113-122

Stantonia spasskensis ; Braet & Quicke, 2004: 1578-1579.

Type material.

Holotype, ♀ (RMNH), "S. Vietnam: Dak Lak, Chu Yang Sin N.P., n[ea]r dam, 740-940 m, 1-10.vi.2007, Mal. traps, C. v. Achterberg & R. de Vries, RMNH’07”. Paratypes (3 ♀): 1 ♀ (IEBR), same data as holotype; 1 ♀ (RMNH), "C. Vietnam: Ha Tinh, Vu Quang N.P., 18°19'47"N, 105°26'28"E, 66 m, 4.iii.-15.iv.2011, Mal. trap 9, C. v. Achterberg & R. de Vries, RMNH’11”; 1 ♀ (ZISP), "Vietnam, pr[ovince] Ha Son Binh, Da Bac, forest bamboo, 22.x.1990, Tuly & Belokobylskij".

Diagnosis.

Antenna with a submedial band consisting of 14-17 ivory or white segments contrasting with blackish or dark brown basal third of antenna (Fig. 112); clypeus moderately convex (Fig. 118); mesosoma entirely black; tegulum and humeral plate dark brown; fore wing evenly infuscated (Fig. 113); hind tarsus (except narrowly basally) whitish or ivory; middle tarsus conspicuously bristly setose; hind femur (except basally) and more or less middle coxa black or dark brown dorsally; first metasomal tergite 3.4-3.6 times as long as wide apically; epipleuron of second metasomal tergite with an isolated and well defined dark brown spot (Fig. 117); second metasomal tergite dark brown to brownish yellow antero-dorsally; length of ovipositor sheath 0.5-0.6 times as long as fore wing; length of fore wing 7.9-9.2 mm.

The new species runs in the key by van Achterberg (1987) to S. annulicornis Enderlein, but differs by having the face yellowish brown and rather densely punctate (pale yellowish and sparsely finely punctate in S. annulicornis ), clypeus partly convex (rather flat), scapus partly infuscated (pale yellow), antenna with 14-17 white or ivory segments submedially (11-12 segments), fore wing evenly slightly infuscate (only apically distinctly infuscate), tegulum dark brown (pale brown or yellowish), and propodeum black medially (more or less yellowish brown or brown).

Description.

Holotype, ♀. Body length 9.7 mm, fore wing length 9.2 mm, ovipositor sheath 4.9 mm.

Head. Antenna with 61 segments and 1.6 times as long as fore wing; middle antennal segments with distinct false division medially and 1.8 times as long as wide; third, fourth and penultimate antennal segments 4.5, 2.9 and 1.8 times as long as wide, respectively, and third segment 1.6 times as long as fourth segment; width of face 0.9 times height of face and clypeus combined (Fig. 118); maxillary palp 1.5 times as long as height of head; malar space 0.7 times as long as mandible width, largely coriaceous and with distinct groove; distance between tentorial pits 2.2 times as long as distance between pit and eye margin; in anterior view length of eye 2.2 times as long as wide; in dorsal view length of eye 3.5 times as long as temple; POL:OD:OOL = 8:10:15; distance between anterior and lateral ocellus 0.5 times OD (Fig. 119); face remotely and moderately punctate, interspaces smooth and much wider than punctures and medium-sized setae; vertex finely remotely punctate and directly behind stemmaticum steeply depressed; temple matt, granulate, punctate and postero-ventrally with rugae; occipital flange wide and lamelliform.

Mesosoma. Length of mesosoma 1.5 times as long as high; pronotal side with complete Y-shaped crenulate grooves, postero-ventrally connected to crenulate border, largely smooth dorsally, partly coarsely punctate and with some rugae ventrally and remainder sparsely finely punctate (Fig. 114); notauli rather narrow and moderately crenulate, but widened posteriorly and ending far in front of scutellar sulcus (Fig. 115); scutellar sulcus smooth, except for some remnants of crenulae posteriorly; mesoscutum and scutellum remotely finely punctate (Fig. 115); precoxal sulcus complete and rather narrowly crenulate (Fig. 114), mesopleuron sparsely finely punctate, but mainly smooth near precoxal sulcus; metapleuron rather densely punctate; propodeum spaced punctate with interspaces smooth and at least as wide as diameter of punctures, rather dull and with few weak transverse rugae (Fig. 115).

Wings. Fore wing (Fig. 113): first discal cell truncate anteriorly; pterostigma 5.0 times as long as wide; r:2-SR:3-SR+SR1:r-m = 20:19:67:10; second submarginal cell narrowly petiolate; r issued behind middle of pterostigma; r-m largely sclerotized; cu-a interstitial; basal three-quarters of CU1a sclerotized; CU1b: 3-CU1 = 10:23, CU1b oblique, distinctly diverging posteriorly from cu-a. Hind wing: M+CU:1-M: 1r-m = 6:21:2; R1 with three distinct hamuli; area in front of cu-a and behind it glabrous.

Legs. Ventrally hind femur rugose, but posteriorly becoming obsolescent, with satin sheen (as outer side); length of femur, tibia and basitarsus of middle leg 5.5, 9.3 and 10.0 times as long as their width, respectively; inner and outer middle tibial spurs 0.45 and 0.30 times as long as basitarsus; middle tarsus very bristly; length of femur, tibia and basitarsus of hind leg 5.0, 8.3 and 6.4 times their width, respectively; inner and outer hind tibial spurs 0.50 and 0.35 times as long as basitarsus, respectively.

Metasoma. First tergite parallel-sided, 3.6 times as long as its apical width, its surface with satin sheen, largely smooth (except some superficial micro-sculpture and some punctures; Fig. 116); second and third tergites smooth (except some punctures and superficial micro-sculpture), and rather dull, except a shiny triangular basal area; second tergite 1.7 times longer than its basal width; length of ovipositor sheath 0.51 times as long as fore wing and 0.9 times as long as metasoma (Fig. 112).

Colour. Black; antenna dark brown but 3 basal antennal segments with pale brownish or greyish spots, 33rd segment pale brown, 17 th– 18th segments partly ivory and 19 th– 32nd segments white; tegulum, humeral plate, apex of middle tibia, patch on second epipleuron, third tergite (except antero-laterally), fourth and fifth tergites largely, sixth tergite dorsally and ovipositor sheath dark brown; middle tibial spurs, inner apex of middle femur, seventh and eight tergites dorsally, brown; tarsi ivory, but telotarsi black, hind basitarsus basally narrowly blackish and middle tarsus dark brown ventrally; coxae, hind femur (except basally), apical third of hind tibia, hind tibial spurs, first (except basal triangle) and second tergites dorsally, black; remainder of legs and of metasoma, palpi and clypeus pale yellowish; face brownish yellow; entire fore wing infuscated; veins and pterostigma dark brown.

Male. Unknown.

Variation.

Length of body 7.2-9.7 mm; length of fore wing 7.0-9.2 mm; antenna with 55(1), 61(2) segments; length of first metasomal tergite 3.6-3.7 times its apical width; length of ovipositor sheath 0.51-0.54 times fore wing; 18 th– 30th or -32nd, or 19 th– 32nd antennal segments white.

Distribution.

Vietnam (Hoa Binh; Ha Tinh (Vu Quang N.P.); Dak Lak (Chu Yang Sin N.P.)).

Notes.

A male from Thanh Son (RMNH) has 14 pale antennal segments, yellow mesopleuron, mesosternum, middle coxa and middle of propodeum, and probably belongs to a related species. Except for having less pale antennal segments than the examined holotype of S. spasskensis , it differs by having vein cu-a of fore wing distinctly postfurcal (slightly antefurcal in S. vietnamica ), less extensive infuscation of fore wing (most of apex of fore wing), and base of T1 yellowish-brown (ivory).