Antepipona concava Nguyen, Dang & A. D. Nguyen, n. sp.

(Figs 11; 12)

urn:lsid:zoobank.org:act: 293164CF-EDE5-4DF1-ABF9-A86846773957

MATERIAL EXAMINED. — Holotype. Vietnam • ♂; Ke Go National Researve, Cam Xuyen, Ha Tinh; 22.VI.2018; Nguyen Quang Cuong leg.; IEBR.

Paratypes. Vietnam • 4 ♂; same data as for holotype; IEBR .

DIAGNOSIS. — This species can be distinguished from congeners by the following character combination: Inner compound eye margins strongly convergent ventrally, in anterior view c. 1.7× further apart from each other at vertex than at clypeus; clypeus with apical margin widely and deeply emarginate medially, forming rather blunt tooth on each side, distance between teeth nearly half width of clypeus between inner compound eye margins (c. 0.45× width of clypeus between inner compound eye margins); propodeum with deep concavities, the concavities shiny and with dense strong punctures, corner between dorsal and posterior surfaces angled, posterior surface without carinae; SII not bulging at base.

DISTRIBUTION. — Central Vietnam.

ETYMOLOGY. — The specific epithet is the Latin adjective concavus, meaning, “concave”, and refers to the deep concavity of the posterior surface of the propodeum in this species.

DESCRIPTION

Male (Fig. 11F)

Measurements. Body length 5.5-6.0 mm (holotype: 5.7 mm); forewing length 5.2-5.8 mm (holotype: 5.5 mm).

Structure. Head in facial view transverse, 1.2× as wide as high (Fig. 11A). Vertex without cephalic fovea. Distance from posterior ocellus to posterior margin of vertex 1.4× distance from posterior ocellus to inner compound eye margin (Fig. 11C). Gena in lateral view narrower than compound eye, about 0.8× as wide as compound eye; occipital carina not complete, present only along length of gena, obsolete dorsally. Inner compound eye margins strongly convergent ventrally, in anterior view c. 1.7× further apart from each other at vertex than at clypeus (Fig. 11A). Clypeus in lateral view gradually convex from base to apical margin; in frontal view slightly wider than high (Fig. 11A), with basal margin slightly concave medially and distinctly separated from antennal toruli; apical margin widely and deeply emarginate medially, forming rather blunt tooth on each side, distance between teeth nearly half width of clypeus between inner compound eye margins (c. 0.45× width of clypeus between inner compound eye margins). Mandible with five prominent teeth. Antennal scape c. 4× as long as its maximum width, slightly curved; FI c. 2× longer than wide, FII slightly longer than wide, FIII-IV as wide as long, FV-FVIII wider than long, FX small, terminal flagellomere slightly curved, long and gradually narrow from base to apex, c. 2.2× as long as its basal width (Fig. 11B).

Mesosoma. Longer than wide in dorsal view (Fig. 11C). Pronotal carina fully developed, reaching ventral corner of pronotum, somewhat weak dorsally; anterior surface of pronotum with two close, deeply impressed pits medially, with dense strong punctures mediolaterally. Mesoscutum weakly convex, slightly longer than wide between tegulae, without depressed and oblique furrows apically (Fig. 11C). Disc of mesoscutellum convex, in lateral view at same level of mesoscutum (Fig. 11D), narrowly depressed basally, with a row of short longitudinal carinae basally and apically. Metanotum weakly convex, with two large and sharp tubercles, distance between tubercles slightly longer than distant from tubercle to lateral margin of metanotum (Fig. 11E). Propodeal dorsum below level with metanotum; declivity of propodeum with strong carina medially; concavity deep and wide, without short carinae (Fig. 11E), corner between lateral and dorsal surfaces angulate, corner between dorsal and posterior surfaces angulate.

Metasomal segment I narrower than segment II (Fig. 11F); TI conical in shape, in dorsal view almost half as long as wide; TII wider than long, about 1.1× as wide as long in dorsal view; SII depressed at base, in lateral view slightly convex from base to apical margin.

Sculpturing. Clypeus with dense strong punctures, interspaces between punctures smooth, larger than puncture diameter at lateral parts, each puncture bearing a short bristle. Frons densely covered with coarse flat-bottomed punctures, interspaces between punctures raised to form reticulations. Vertex with punctures similar with those on frons, but larger; gena with large strong punctures, punctures weaker and smaller near base; occipital carina weakly widened laterally (Fig. 11D). Pronotum with punctures coarser than those on vertex, interspaces between punctures thicker and raised to form reticulation. Mesoscutum covered with coarse punctures, punctures equal in size, smaller than those on pronotum, interspaces between punctures smooth, raised to form reticulations; mesoscutellum with punctures similar to those on pronotum, punctures on metanotum smaller than those on mesoscutellum. Mesepisternum with flat-bottomed punctures similar to those on pronotum posterodorsally, smooth anteroventrally; border between posterodorsal and anteroventral parts distinct, without epicnemial carina. Dorsal part of metapleuron largely smooth and with several short weak striae, ventral part with sparse shallow punctures. Propodeum with coarse punctures dorsally, interspaces between punctures strongly raised to form reticulation, punctures much shallower and weaker laterally, dorso-lateral margin of propodeum somewhat angled; posterior surface shiny, with dense strong punctures.Tegula with minute punctures. Metasomal TI covered with dense strong punctures, punctures on lateral and apical margins sparser and weaker; punctures on TII smaller and shallower than those on TI, punctures on apical margin of TIII-IV larger than those on apical margin of TII, punctures on apical margin of TV-VI smaller than those on apical margin of TIII-TIV, punctures on TVII and SVII small and sparse, punctures on SII clear, deeper than those on TII, interspaces with minute punctures.

Color. Body black, with following parts yellow: clypeus except apical margin, a large spot on frons, a large mark along inner orbit to clypeus, mandible except base and teeth, antennal scape except a longitudinal black strip dorsally, two spots on vertex below compound eye margins, two large spots on pronotum, two large spots on mesoscutellum and two smaller spots on metanotum, a large spot on mesopleuron, two very large spots on propodeum laterally, tegulae except large brown-black spots centrally and parategulae, two large spots on TI laterally and apical margin, two large spots laterally and a thick band apically on TII, bands on TIII and TIV laterally, two small spots at lower corner laterally on SIII and SIV, apical margin of TV-TVI, coxae of all legs except dorsal part black, all femora except dorsal part brown on profemur and black on mesofemur and apex of metafemur. Valvulae brown. Wing membrane transparent, veins dark brown (Fig. 11F).

Pubescence. Body with silver setae of medium-length.

Genitalia. As in Figure 12. Parameral spine without setae. Volsella flattened, spatulate, wide on inner aspect, without setae at top (Fig. 12A). Digitus with very dense and long setae (Fig. 12B). Penis valves short (Fig. 12C), about 1.7× as long as basal apodeme, in ventral view with small tubercle at base of basal apodeme, in profile apical part strongly produced into a large triangle lobe (Fig. 12D), smooth, without teeth.

Female

Unknown.

REMARKS

This species is quite similar to A. ovalis (de Saussure, 1853) in having the posterior surface of the propodeum without carinae, SII not bulging at base, clypeus wider than long, punctures on metasoma dense and strong, but it differs from the latter by the following characters: clypeus slightly wider than high (clypeus in frontal view about 1.3× as wide as high in A. ovalis); metanotum with two large sharp tubercles (metanotum with two small blunt tubercles in A. ovalis); propodeum angled laterally (propodeum rounded laterally in A. ovalis); posterior surface of propodeum deeply concave, with dense strong punctures, corner between dorsal and posterior surfaces angled (posterior surface of propodeum shallowly concave, with sparse small punctures, corner between dorsal and posterior surfaces rounded in A. ovalis).