Parapolybia flava Saito-Morooka, Nguyen & Kojima, sp. nov.

(Figs 41–52, 80, 86)

Parapolybia indica indica (?): van der Vecht 1966: 29, part.

Diagnosis. This species can be distinguished from other species of the P. i n di ca species-group by the combination of the following characters: female gena well developed, swollen posterolaterally; in both sexes, T2 distinctly concave on both sides of median line.

Type material. HOLOTYPE: ♀, VIETNAM: Thanh Cong, Nguyen Binh, Cao Bang Prov., 22°32.5'N, 105°52'E, 700 m, 7.viii.2012, J. Kojima & H. Nugroho, nest# VN-NE2012-Pp-10” [IUNH, long-term loan from IEBR], PARATYPES: VIETNAM: Cao Bang: 7 ♀ 2 ♂ [IUNH], Thanh Cong, Nguyen Binh, J. Kojima & H.

Nugroho, [5 ♀ 2 ♂, 22°32.5'N, 105°52'E, 700 m, 7.viii.2012, nest# VN-NE2012-Pp-10; 3 ♀, 22°34'N, 105°52.5'E, 1000 m, 9.viii.2012, nest# VN-NE2012-Pp-11]; 6 ♀ [IUNH], Nguyen Binh, Thanh Cong, J. Kojima, H. Nugroho & IED-c [4 ♀, 22°34'N, 105°53'E; 1 ♀, 22°32.5'N, 105°52'E]; Bac Kan: 4 ♀ 1 ♂ [IUNH], Na Ri, 22°12'51''N, 105°58'42''E, 550 m, 5.viii.2012, J. Kojima & H. Nugroho, nest# VN-NE2012-Pp-09; Ha Tinh: 700 m, 30.v.2004, L.T.P. Nguyen.

Description. FEMALE. Body length 15.0–18.0 mm; fore wing length 14.0– 15.5 mm. Head in frontal view 1.1 × as wide as high (Fig. 41). Gena developed, swollen laterally, in frontal view of head visible in its entire height (Fig. 41), in lateral view about as wide as eye (Fig. 42). Ocelli close to each other (Fig. 43); distance between anterior and posterior ocelli shorter than Od; POD less than their Od; anterior ocellus diameter 0.20–0.24 mm, posterior ocellus diameter 0.20–0.24 mm; OOD 2.0 × as large as Od. Propodeum finely and shallowly striate in anterior half, deeper posteriorly. T1 posteriorly swollen (4.0–5.0 mm long, Figs 44–45), 3.0 × longer than the maximum height, 3.0 × as long as its own maximum width. T2 distinctly depressed sublaterally (Fig. 46).

Color. Body yellow (Fig. 80), with following parts brown to dark brown: dorsal part of scape, pedicel, basal half of flagellum (varying between individuals), paired ill-defined spots on clypeus, frons, vertex, anterior spot and line along posterodorsal margin of pronotum, median longitudinal band of mesoscutum, scutellum, tegula, median longitudinal band of propodeum, anterodorsal half of T1, anterior half of S1, S2–S6 except for dorsal yellow markings (remarkably varying in size and shape), basal spot of mid and hind femerora, basal half of mid and hind tibiae. Following parts black: anterior margin of clypeus, teeth of mandible, margin of ocelli, anterior margin and posterior line of mesoscutum, groove of mesopleuron, mid and hind tarsi.

MALE. Body length about 13.0 mm; fore wing length 12.0 mm. Head in frontal view 1.1 × higher than wide (Fig. 47). Eye enlarged. Ocelli close to each other (Fig. 48); distance between anterior and posterior ocelli less than half of Od; POD about half of their Od; anterior ocellus diameter 0.24–0.26 mm, posterior ocellus diameter 0.22– 0.24 mm; OOD 1.3 × as Od. Antenna thin and long, F11 2.0 × as long as F10. T1 not robust (about 3.5 mm, Figs 49–50), 3.0 × longer than its maximum height, 3.0 × as long as its own maximum width. T2 distinctly depressed sublaterally (Fig. 46). Legs thin and long, hind tibia 4 mm. Volsella elongate. Digitus broadly bulged, strongly bend inward. Parameral spine short, with dense hairy setae (Fig. 51). Proximal margin of aedeagus ventrally produced (Fig. 52).

Color. Body light yellow (Fig. 80); following parts light brown to orange: mesoscutum and scutellum; following parts brown to dark brown: dorsal part of scape, pedicel, dorsal side of flagellum (darker basally), frons, vertex, anterial mark and dorsolateral line of pronotum, median line and anterior margin of mesoscutum, median line of scutellum, median and dorsolateral lines of propodeum, groove on mesopleuron, dorsal mark of T1, T2 except for paired large yellow spots, tarsi.

Etymology. The specific name originates from a Latin flavus with reference to the body coloration.

Distribution. Vietnam (North Vietnam).