Zethus velamellatus Tan, 2018

Tan, Jiang-Li, Carpenter, James M & Achterberg, Cornelis van, 2018, Most northern Oriental distribution of Zethus Fabricius (Hymenoptera, Vespidae, Eumeninae), with a new species from China, Journal of Hymenoptera Research 62, pp. 1-13 : 1

Zethus velamellatus Tan sp. n.

Figs 14 , 15-24

Material examined.

Holotype, ♀ ( NWUX): " CHINA: Zhejiang, Hangzhou, Lin’an, Qingliangfeng , Shunxi , N30.06° E118.94°, 23.viii.2013, Jiangli Tan ".

Diagnosis.

Clypeus of ♀ punctate-reticulate and depressed space between apical teeth without median ridge; mesopleuron reticulate-rugose; propodeal lamella almost invisible as the submarginal carina is not produced above propodeal valvulae; T1 unevenly punctate and approx. twice as long as its maximum width in dorsal view and approx. 2.4 × as long as high in lateral view; SI densely striate and sparsely punctate; TI with apical yellow band.

Description.

Length of body 13.0 mm; fore wing length 11 mm; width of mesonotum (including tegulae) 3.1 mm.

Head. Head transversely oblong, approx. 1.3 × wider than high in anterior view (Fig. 20 ), about 2.2 × wider than long in dorsal view, coarsely punctate-reticulate and with long setae. Temple contracted behind eyes, approx. 1.2 × wider than eye in dorsal view. Occipital carina developed, with crenulae in front of it. Clypeus gently convex, slightly less than twice as wide as long, emarginated at basal margin; apex minutely bi-dentate, depressed space between both teeth without median ridge (Fig. 21 ); clypeus punctate-reticulate with dense yellowish brown long setae (more than three times ocellar diameter); width of apical depression about a quarter width of clypeus. Mandible with four teeth, coarsely punctate-rugose, third and fourth teeth truncated. Antennal scape punctate, 2.7 × as long as its maximum width; FI 1.9 × as long as its maximum width, FII as long as wide, FIII-IX wider than long, FX bullet-shaped, as long as its basal width (Fig. 22 ).

Mesosoma. Pronotum reticulate-punctate dorsally with ventro-lateral area punctate-rugose (Fig. 15-16 ). Mesoscutum coarsely rugose-punctate to densely punctate (Fig. 15 ); mesoscutellum and metanotum coarsely punctate with distance between punctures less than diameter of puncture. Epicnemial carina distinct, bordered posteriorly by a narrow sulcus; episternal sulcus indistinctly developed as a crenulate depression, epipleural suture indistinct; mesopleuron (episternum) coarsely punctate-rugose (Fig. 16 ), below pleural and epipleural sulci densely punctate-rugose with epicnemium and posterior part of episternum coriaceous (Fig. 16 ). Propodeum coriaceous-aciculate laterally and without lateral carina (Fig. 17 ), coriaceous-reticulate postero-laterally and oblique punctate-rugose along each side of median carina and with dense setae (Fig. 17 ); submarginal carina not produced into a lamella resulting in absence of propodeal lamella above propodeal valvula (Fig. 17 ).

Metasoma. TI short, about twice as long as wide in dorsal view, gradually widened from base to basal one third, then slightly narrowed toward apex, with maximum width 3.1 × its basal width (Fig. 17 ); in lateral view smoothly curved between basal stem and apical part; strongly convex dorsally, about 2.4 × as long as high (Fig. 18 ); TI unevenly punctate; SI densely striate and sparsely punctate (Fig. 19 ). TII sparsely punctate with rather short petiole basally, about 1.4 × as long as wide in dorsal view (Figs 23 , 24 ); SII in lateral view smoothly curved from base to apical margin (Fig. 23 ); TII and SII with raised apical lamella of approx. 0.2 mm and 0.1 mm long, respectively, apical lamella of TIII flat and approx. 0.25 mm long.

Colour (Figs 14 - 19 ). Body black, except a yellow spot near dorso-inner margin of antennal socket, a pair of transverse yellow lateral spots on apical margin of TI, TII with a narrow yellow subapical band and propodeal valvula yellowish brown. Wings yellowish brown tinged.

Remarks.

Zethus velamellatus sp. n. fits well into the Zethus trimaculatus -group ( Giordani Soika 1958, Yeh and Lu 2017) in sharing the main character of a short and stout first metasomal segment. The new species is easily to separate because of the missing submarginal lamella of the propodeum, the punctate sculpture of SI and smoothly curved profile of SII in lateral view.

Distribution.

China (Zhejiang).

Etymology.

This species is named " Zethus velamellatus ( “ve” is Latin for “without”) because the propodeal lamella is invisible in this species.

Figures

Figure 14. Zethus velamellatus Tan, sp. n., holotype, ♀, habitus, lateral aspect.

Figures 15 - 24. Zethus velamellatus Tan, sp. n., holotype, ♀. 15 Head and mesosoma, dorsal aspect 16 head and mesosoma, lateral aspect 17 propodeum and TI, dorsal aspect 18 propodeum and TI, lateral aspect 19 SI, ventral aspect 20 head, anterior aspect 21 clypeus, anterior aspect 22 antenna 23 metasoma, lateral aspect 24 metasoma, dorsal aspect.