Zethus striatus Wang & Li, 2019

Wang, Hua-Chuan, Chen, Bin & Li, Ting-Jing, 2019, Three new species of the genus Zethus Fabricius, 1804 (Hymenoptera, Vespidae, Eumeninae) from China, with an updated key to the Oriental species, Journal of Hymenoptera Research 71, pp. 209-224 : 211-212

Zethus striatus Wang & Li sp. nov.

Figs 1-12

Material examined.

Holotype, ♀: CHINA, Guangxi, Baise City, Tianlin County, CengWangLaoShan National Nature Reserve , Dalongping , 24°29.361'N, 106°24.076'E, 24-25.VIII.2007, Xiang Li leg. (CQNU).

Description.

Female: body length 15.3 mm ( Fig. 1 ), fore wing length 13.7 mm. Black, the following parts yellow: clypeus except base and central middle, spot on dorso-inner margin of antennal socket, antennal scape ventrally, paired transverse middle spots on dorsal side of pronotum, apical bands on T1 and T2; tegula dark brown ( Fig. 5 ).

Head. Head with short setae, their length slightly longer than posterior ocellar diameter; head about 2.1 × wider than long in dorsal view ( Fig. 2 ), wider than high in frontal view, about 1.2 × as wide as high ( Fig. 3 ); mandible with four blunt teeth and short setae; clypeus convex in lateral view and about 1.3 × as wide as high in frontal view, with basal margin nearly straight, apical margin of clypeus frontally truncated and laterally cambered, clypeus punctate-reticulate with sparse setae ( Fig. 3 ); frons with sparse setae and dense punctures; vertex and gena with dense punctures; gena in lateral view as wide as eye, without longitudinal carina; distance from posterior ocelli to apical margin of vertex 1.7 × as long as distance from posterior ocelli to inner eye margin ( Fig. 2 ); occipital carina developed laterally and weak dorsally ( Fig. 4 ); antennal scape 3 × as long as its maximum width, A3 1.4 × as long as its maximum width, A4 as long as its maximum width, A5-11 wider than long, A12 bullet-shaped, as long as its basal width.

Mesosoma. Length of mesosoma about 1.3 × as long as wide in dorsal view ( Fig. 5 ); pronotal carina weak laterally and indistinct dorsally, pronotum with dense punctures and slightly reticulate dorsally; notaulix distinct on basal half of mesoscutum, mesoscutum with deep and dense punctures, area between punctures striate, in lateral view weakly convex; tegula smooth, with very sparse punctures, its posterior lobe triangular and well developed which exceeds parategula posteriorly; epicnemial carina distinct; mesopleura with deep and dense punctures, slightly sparse ventrally; scutellum flattened, with deep and dense punctures, area between punctures striate, longitudinal furrow on the middle of scutellum ( Fig. 5 ); metanotum sloping down posteriorly, with deep punctures; metapleuron almost smooth; propodeum ( Fig. 6 ) with strong striae and lateral carina, its dorsolateral surface with distinct and oblique striae and strong longitudinal carina along submedian carina, posterior surface of propodeum with transverse striae along median carina, submarginal carina produced into lamella above propodeal valvulae, its lateral surface with punctures along lateral carina and weak striae on its lower half ( Fig. 7 ); orifice more or less angled dorsally ( Fig. 6 ).

Metasoma. T1 about 2.5 × as long as wide in dorsal view, gradually widening from one-third of the base, then nearly parallel-sided apically, with maximum width 3 × its basal width, without medial carina, T1 with deep and dense macropunctures and sparse setae ( Fig. 10 ), lateral carina of T1 present in ventral view ( Fig. 11 ); BS of S1 with median longitudinal carina and narrow from its middle to apex, coarsely punctate on apical margin of BS and base half of AE ( Fig. 11 ); T2 without petiole and with developed apical lamella, about 1.2 × as long as wide in dorsal view, T2 with deep and dense punctures ( Fig. 12 ); S2 swollen from the base to near midpoint, subsequent portion nearly straight in profile ( Fig. 8 ), its apical margin with lamella; T3 with developed and raised apical lamella ( Figs 8 , 9 , 12 ); subsequent terga and sterna with deep punctures, but slightly smaller than those on T2.

Male.

Unknown.

Distribution.

China: Guangxi.

Remarks.

The species is similar to Z. trimaculatus Cameron, 1904 from Vietnam, Laos and India by the characters: body with dense punctures ( Fig. 1 ), occipital carina developed laterally and weak dorsally ( Fig. 4 ), pronotal carina weak laterally and indistinct dorsally ( Fig. 5 ), S2 not tuberculate in profile ( Fig. 8 ). It differs from Z. trimaculatus and all other members of the genus by the following character combination: apex of clypeus yellow, apical margin of clypeus frontally truncated ( Fig. 3 ) and laterally cambered, BS of S1 with longitudinal carina ( Fig. 11 ), propodeum with strong lateral carina and its dorsolateral and posterior surface with strong striae ( Fig. 6 ).

Etymology.

The specific name Zethus striatus is derived from Latin word: Zethus striatus , referring to propodeum with strong striae in dorsal view.

Figures

Figures 1 - 12. Zethus striatus sp. nov., holotype 1 habitus in dorsal view, ♀ 2 vertex, ♀ 3 head in frontal view, ♀ 4 vertex in dorsal-lateral view, ♀ 5 mesosoma, ♀ 6 propodeum in dorsal view, ♀ 7 propodeum in lateral view, ♀ 8 metasoma in lateral view, ♀ 9 metasoma in dorsal view, ♀ 10 T 1, ♀ 11 S 1, ♀ 12 T 2, ♀.