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

(Figs 65–69, 81, 82)

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

Diagnosis. This species is similar in the external morphology to P. i n di c a and P. c ro c ea sp. nov., but can be easily distinguished from the latters by the female vertex behind the posterior ocelli sloping down to the occipital carina after a narrower flat area.

Type material. HOLOTYPE: ♀, VIETNAM: Mai Chau, Pa Co, Hoa Binh Prov., 20°44.5'N, 104°53.5'E, ca. 1450 m, 27.viii.2006, L.T.P. Nguyen, F. Saito & J. Kojima, nest# VN-Pp- 2006-16 ” [IUNH, long-term loan from IEBR]. PARATYPES: VIETNAM: Hoa Binh: 7 ♀ with same data as holotype [IEBR, IUNH].

Description. FEMALE. Body length about 14.0 mm; fore wing length 12.5–14.0 mm. Head in frontal view 1.1 × as wide as high (Fig. 65). Gena barely swollen laterally, in frontal view of head invisible (Fig. 65), in lateral view 0.7 × as wide as eye (Fig. 66). Vertex behind posterior ocelli sloping down to occipital carina after narrow flat area (Fig. 82). Ocelli close to each other (Fig. 67); distance between anterior and posterior ocelli shorter than Od; POD less than their Od; anterior ocellus diameter 0.25 mm, Od 0.20 mm; OOD 2.0 × as large as Od. Propodeum with fine shallow transverse striae in anterior one third, striation stronger and deeper posteriorly. T1 thin and long (about 3.8 mm long, Figs 68–69), 3.5 × longer than the maximum height, 3.0 × as long as its own maximum width.

Color. Similar to P. crocea, but ambiguous paired brown spots on clypeus and metasoma distinctly darker (Fig. 81) as follows: segments 2–6 brown to dark brown, with paler colored lateral spots on T2.

MALE. Unknown.

Etymology. The specific name originates from a Latin nanus with reference to the appearance. Distribution. Vietnam (North Vietnam).