Brachyzapus politus Pham & Broad & Matsumoto & Wägele 2012, sp. nov.

(Figure 6)

Material examined

Holotype (female). Lao Cai, Hoang Lien NP, 1550 m a.s.l., 22–29 October 1999, Malaise trap, C. v. Achterberg leg. (RMNH).

Diagnosis

Inner margins of eyes distinctly convergent ventrally; face narrow, 1.9 × as high as wide, sparsely finely punctate; malar space short, 0.25 × basal width of mandible; notauli present basally, indistinct posteriorly; scutellum with lateral carina strong to middle, without lateral transverse ridges; propodeum dorsally sparsely punctate, laterally with some transverse ridges at level of posterior transverse carina; first sternite convex, angled apically.

Description

Body length 8 mm, fore wing 5.5 mm, ovipositor 1.9 mm.

Head. Antenna with 25 flagellomeres, first flagellomere 1.4 × length of second; diameter of lateral ocellus 1.2 × ocellar–ocular distance; frons impunctate, polished; inner margins of eyes distinctly convergent ventrally; face narrow, 1.9 × as high as wide, subpolished, with very small punctures, upper margin concave between antennal sockets; clypeus strongly convex, about 0.75 × as high as wide, apical margin thin, emarginate; malar space 0.25 × basal width of mandible; mandible weakly twisted, narrow, upper tooth slightly longer than lower tooth; occipital carina complete, meeting hypostomal carina about 1.3 × basal mandible width from base of mandible.

Mesosoma. Epomia length 2 × basal mandible width; pronotum impunctate and polished laterally, punctate and pubescent dorsally; mesoscutum densely setose with notauli moderately deep on basal 0.3, indistinct posteriorly; scutellum strongly convex, pubescent, lateral carina extending to middle; mesopleuron moderately densely setose except posterior concave area near mesopleural suture bare and polished, mesopleural suture foveolate, epicnemial carina present on lower 0.6 of mesopleuron; metapleuron bare and polished medially, pubescent basally, dorsally and apically, submetapleural carina forming small lobe anteriorly and angled about 135 ◦ posteriorly; metasternum with transverse ridge from posterior angulation of submetapleural carina extending about 0.6 × distance to median longitudinal groove; propodeum moderately convex, pubescent, except dorso-medially and petiolar area polished, posterior stub of lateral longitudinal carina present, several transverse ridges present at level of posterior transverse carina laterally. Legs with mid and hind tibiae slightly swollen sub-basally; fore femur 3.4 × as long as wide; hind femur 4.5 × as long as wide, length 0.8 × tibia, tibia 9 × as long as apical width; basitarsus longer than following three segments combined, length 0.33 × tibia, 0.45 × tarsus, 3 × second tarsomere, fourth tarsomere very short, fifth 2 × as long as third. Fore wing with vein Rs & M slightly basad of cu-a, 2 rs-m about 0.7 × distance between 2 rs-m and 2 m-cu, vein cu-a slightly inclivous, vein Cu 1 a separated from 1 m-cu by 1.15 × length of vein Cu 1 b; hind wing with first abscissa of vein Cu 1 as long as vein cu-a.

Metasoma. Metasoma 2 × longer than head and mesosoma combined; tergites coriaceous, with scattered short hairs; first tergite 2.3 × as long as apical width, dorsolateral carina complete, median longitudinal carina extending to oblique groove; second tergite 0.9 × length of first tergite, 1.5 × as long as apical width, basal and apical oblique grooves moderately deep, rhombic area moderately convex; third tergite shorter than second, basal and apical oblique grooves weakly present; first sternite with some transverse ridges at base, convex and angled apically; ovipositor straight, length from tip of hypopygium slightly longer than hind tibia, basal half of upper valve slightly swollen, tapered to sharp point.

Colour. Black. Antenna yellowish brown, mandible brown, palpi and tegula yellow; legs reddish brown, except fore and mid coxae yellow, hind tibia with sub-basal and apical fuscous bands; wings hyaline, pterostigma and veins brownish yellow; ovipositor reddish brown.

Male. Unknown.

Distribution

Currently known only from Hoang Lien NP, Lao Cai Province, North Vietnam (Figure 7).

Ecological notes

The single specimen was collected in montane evergreen forest at an elevation of 1550 m a.s.l.

Comparison

Brachyzapus politus sp. nov. resembles B. tenuiabdominalis but it can be distinguished from the latter by its sparsely punctate face, gena and dorsal face of the propodeum; the weakly curved epicnemial carina; its less angled mesopleural suture; the longer median longitudinal carinae of the first tergite, extending to the posterior, transverse smooth band; and the second tergite with distinct, basal, oblique grooves. The new species differs from other Vietnamese Brachyzapus species by the notauli present only on the basal 0.3 of the mesoscutum, not meeting in the posterior half; the propodeum with the posterior transverse carina absent; the scutellum and post-scutellum black; and the strong lateral carina of the scutellum, extending to the middle.

Etymology

This species is named after its polished face, gena and dorsal face of the propodeum.