Tamdaona brevizona van Achterberg, sp. n.

Figs 65–78)

Type material. Holotype, ♀ (RMNH), “ Vietnam: Ninh Thân, Núi Chúa N.P., dry south part, 100–180 m, Mal[aise] traps], 22–29.v.2007, C. v. Achterberg & R. de Vries, RMNH’07” . Paratypes: 1 ♀ (IEBR), with same data as ho- lotype; 1 ♀ (RMNH), “ S. Vietnam: Dak Lak, Chu Yang Sin N.P., n[ea] r dam, c. 500 m, c. 500 m, Mal[aise] traps], 3–9.vi.2007, C. v. Achterberg & R. de Vries, RMNH’07” .

Description. Holotype, ♀, length of fore wing 1.8 mm, and of body 2.2 mm.

Diagnosis. Antenna of ♀ with 20 or 21 antennomeres (Fig. 65); frons without medio-longitudinal depression (Fig. 74); rim of mesoscutum dark brown near tegulae (Fig. 70); notauli rather wide anteriorly (Fig. 70); mesosoma ventrally and more or less posteriorly yellowish brown (Fig. 69); propodeum gradually lowered posteriorly (Fig. 65); vein 3-SR of fore wing 1.1–1.2 × as long as vein r (Fig. 67); vein 1-R1 1.1–1.3 × longer than pterostigma (Fig. 67); second submarginal cell of fore wing distinctly narrowed anteriorly (Figs 65, 67); legs pale yellowish; basal area of second metasomal tergite transverse and finely reticulate (Fig. 71), narrow and medially 0.10–0.15 × as long as wide anteriorly, hardly or not protruding medio-posteriorly (Fig. 71); second tergite rather transverse and 1.2–1.3 × as long as third tergite (Fig. 71); second metasomal suture rather wide medially (Fig. 71); fourth and fifth tergites largely smooth (Figs 71); setose part of ovipositor sheath 0.33–0.38 × as long as fore wing (Fig. 65).

Head. Antenna with 21 antennomeres, scapus longer dorsally than ventrally (Fig. 65), length of third antennomere 1.2 × fourth antennomere, third, fourth and penultimate antennomeres 2.7, 2.3 and 2.0 × as long as wide, respectively (Figs 76, 77); maxillary and labial palpi with 6 and 4 segments, respectively; length of maxillary palp equal to height of head; temple smooth; hypostomal flange narrow; eye 4.0 × as long as temple in dorsal view; temples directly narrowed behind eyes (Fig. 74); OOL:diameter of posterior ocellus:POL = 30:14:14; vertex and frons largely smooth and shiny, but near eye superficially micro-sculptured and vertex distinctly setose; face remotely punctulate, shiny and convex (Fig. 73); clypeus truncate medially and ventral rim thin, medially moderately convex and with some punctures; hypoclypeal depression 0.4 × as wide as face, medium-sized and rather shallow; malar suture absent; length of malar space 1.2 × basal width of mandible; mandible rather flat medially and smooth, strongly narrowed and twisted apically.

Mesosoma. Length of mesosoma 1.5 × its height; pronotum partly horizontal anteriorly and with large slit-like pronope (Fig. 70); side of pronotum smooth, but with some crenulae anteriorly (Fig. 69); mesopleuron convex, shiny and smooth; precoxal sulcus present as short oblique groove medially with some fine crenulae; episternal scrobe present, linear; pleural sulcus smooth except for some indistinct micro-crenulation ventrally; mesosternal suture deep, narrow and micro-crenulate; notauli complete, smooth, moderately wide and distinctly impressed (Fig. 70); mesoscutum convex, strongly shiny, and largely smooth, setose except middle of lateral lobes and medio-posteriorly with longitudinal groove between notauli; scutellar sulcus narrowed laterally and with one long crenula and some micro-crenulation (Fig. 70); scutellum wide, distinctly convex, setose, largely smooth and shiny; metapleuron largely smooth; propodeum evenly convex, shiny and largely smooth but dorsally micro-sculptured and some rugulae (Fig. 71), only posteriorly with pair of short carina and anterior half with medio-longitudinal carina.

Wings. Fore wing: pterostigma triangular (Fig. 67); second submarginal cell distinctly narrowed anteriorly (Fig. 67); 1-SR much longer than wide; 1-SR+M present anteriorly, but very narrow; 1-R1 1.3 × longer than pterostigma; vein r emitted from middle of pterostigma and slender; r:3-SR:SR1:2-SR = 10:11:64:20; vein SR1 nearly straight; m-cu antefurcal; 1-CU1 widened, about as long as cu-a; 1-CU1:2-CU1 = 1:7; CU1b complete; basal and subbasal cells of fore wing similarly setose as other cells. Hind wing: M+CU:1-M:1r-m = 21:40:13; basal and subbasal cells less densely setose than other cells; m-cu faintly indicated.

Legs. Hind coxa smooth; tarsal claws medium-sized and simple (Fig. 78); length of femur, tibia and basitarsus of hind leg 3.6, 8.8 and 5.1 × as long as their maximum width; hind tibial spurs 0.35 × as long as basitarsus.

Metasoma. First tergite 0.9 × longer than its apical width, gradually widened apically, convex, densely rugulose, shiny, dorsope absent, its dorsal carinae coarsely developed basally, converging, posteriorly weakly developed and merging in sculpture (Fig. 71); first tergite laterally with deep elliptical laterope in smooth glymma; second tergite and most of third tergite densely reticulate-rugulose (including basal area), following tergites largely smooth (Fig. 71); basal area of second tergite transverse and finely reticulate, narrow triangular and medially 0.13 × as long as combined second and third tergites; second metasomal suture and antero-lateral grooves of third tergite distinct and crenulate (Fig. 71); epipleura of second and third tergites semi-transparent; ovipositor sheath subparallel-sided and apically pointed, its setose part 0.38 × as long as fore wing, 2.2 × first tergite and 4.0 × hind basitarsus; ovipositor slightly compressed and hardly widened subapically, with small subapical nodus.

Colour. Yellowish brown; palpi, mouth parts and metasoma ventrally (except apically) white; scapus largely, pedicellus ventrally, tegulae and legs (but telotarsi dark brown) pale yellowish; remainder of antenna, stemmaticum, narrow stripe in front of tegulae, metanotum, propodeum, first tergite (except posteriorly), second tergite (except laterally) and third tergite medio-anteriorly dark brown or brown; pterostigma and most veins of fore wing (except basally) brown; wing membrane subhyaline.

Variation. Length of fore wing 1.7–1.9 mm and of body 2.2–2.4 mm; antennal segments of ♀ 20(1), 21(1); se- tose part of ovipositor sheath 0.33–0.38 × as long as fore wing; propodeum brown or dark brown; fourth metasomal tergite smooth or faintly micro-sculptured.

Etymology. Named after the comparatively short basal area of the second tergite: “brevis” is Latin for “short” and “zona” for “area”.

Distribution. Oriental: Vietnam. Collected in coastal open forest at 100–180 m and lowland forest at 500 m.