Labus robustus Li & Carpenter, 2018

Li, Ting-Jing & Carpenter, James M., 2018, A taxonomic account of the genus Labus de Saussure, 1867 (Hymenoptera, Vespidae, Eumeninae) with descriptions of three new species, Journal of Hymenoptera Research 65, pp. 23-46 : 23

Labus robustus Li & Carpenter sp. n.

Figs 13-16

Material examined.

Holotype, ♂, Indonesia, W. Java, Kereteg , 10.VI.1965, J.E. Lukavsky, deposited in AMNH.

Description.

Male (Figs 13-14 ): body length 7.0 mm. Body black, with the following parts yellow: clypeus except anterior margin (Fig. 14 ), basal part of mandible, two anterior angles of pronotum; a small spot on upper part of mesepisternum; outer margins of tegula, parategula; two transverse nearly elliptical spots on scutellum posteriorly; apical lamellae of propodeum, small apical spots of fore and mid femora inside, outer sides of fore and mid tibiae, basal half at outer side of hind tibiae, narrow apical bands of T1-T2 and S2; apex of mandible, and fore and mid tibiae with exception of yellow spots dark ferruginous; A13 yellowish brown. Wings slightly infuscated.

Head. Head in front view (Fig. 14 ) wide slightly longer than (1.09 ×) high, its sides somewhat flattened; clypeus sparsely setose and shiny, punctures indistinct, clypeal width as long as length, weakly convex at basal half, anterior and median portion produced and with U-formed emargination, the emargination width 1.75 × its depth and teeth acute, clypeal total width 4.86 × its apical width; frons convex, coarsely and densely punctate, and with a longitudinal furrow in the middle, inter-antennal carina not continued on lower part of frons.

Mesosoma. Anterior angles of pronotum projecting moderately, pronotal anterior and transverse carina present, punctures on pronotum, mesoscutum and scutellum similar to those on frons; mesepisternum coarsely punctate and punctures slightly denser than that of other parts; metanotum with a small tubercle in the middle; propodeum posteriorly on each side with a moderate tooth above the apical spine formed by the submarginal carina (Fig. 15 ); dorsal area of propodeum sparsely punctate and the interspaces between punctures coriaceous, posterior area with dense setae, lateral area dull, coarse, and slightly rugose.

Metasoma. Metasomal petiole (Fig. 16 ) short and stout, total length of petiole 4.32 × basal width and 2.16 × apical width, swollen part of metasomal petiole as long as half of the length of the petiole and shiny with scattered minute punctures; linear part of petiole distinctly rugosely punctate and relatively wider and stouter than other species of the genus excluding L. postpetiolatus Gusenleitner; T2 and S2 with apical translucent lamellae, and sparsely covered with extremely minute and shallow punctures.

Distribution.

Indonesia (Java).

Remarks.

This species resembles L. postpetiolatus Gusenleitner, 1988 from Thailand by metasomal petiole short and stout, its total length about 4.5 × basal width, and its linear part distinctly rugosely punctate (Figs 16 , 19 ). It differs from L. postpetiolatus and all other members of the genus by the following character combination: the tooth above the apical spine of propodeum comparatively blunter, lower, and closer to the apical spine (Fig. 15 ); swollen part of metasomal petiole sparsely punctate (Fig. 16 ), in L. postpetiolatus punctures more densely punctate (Fig. 19 ).

Etymology.

The specific name is derived from one Latin word: robustus, referring to metasomal petiole stout.

Figures

Figures 13 - 19. 13 - 16 Labus robustus sp. n., holotype 13 habitus in dorsal view, ♂ 14 Head in frontal view, ♂ 15 propodeum in lateral view, ♂ 16 metasomal petiole, ♂ 17 - 19 Labus postpetiolatus Gusenleitner, 1988. 17 habitus in dorsal view, ♀ 18 propodeum in lateral view, ♀ 19 metasomal petiole, ♀.