Zethus Fabricius, 1804

Pannure, Arati & Carpenter, James M., 2016, Taxonomic studies on potter wasps (Hymenoptera: Vespidae: Eumeninae) of south India, Zootaxa 4171 (1), pp. 1-50 : 42-43

Genus Zethus Fabricius, 1804

Zethus Fabricius 1804: 282 , genus (6 species). Type species: " Zethus coeruleopennis Fab. " [= Vespa coeruleopennis Fabricius, 1798 ], by subsequent designation ( Latreille 1810: 328, 438). Senior objective synonym of Euzethus Dalla Torre, 1904 ; senior subjective synonym of Didymogastra Perty, 1833 , Wettsteinia Dalla Torre, 1904 and of Laboides Zavattari, 1912 ; senior synonym of Heros de Saussure, 1855 according to Bohart & Stange 1965: 25.

Zethus: Giordani Soika 1960 (1958) : 75–80; Bohart & Stange 1965: 25, mentioned Ashmead (1902) as the author who designated Vespa coeruleopennis Fabricius as the type species.

Diagnosis. Mandibles short, not distinctly cross each other, teeth clustered towards apex. Clypeus wider than long, generally with truncate apical margin. Cephalic fovea absent. Mesosoma more or less flattened dorso-ventrally, distinctly longer than high. Anterior face of pronotum without medial pits/foveae. Pronotal carina complete. Epicnemial carina present. Pretegular carina weakly developed. Mesoscutum with notauli present. Tegula much longer than broad, with distinct emargination on its posterior margin where it adjoins parategula, posterior end much exceeding end of parategula. Metanotum oblique, not dentate. Axillary fossa wide. Propodeum with no dorsum behind metanotum, not forming shelf. Superior carina absent. Propodeal orifice narrowly acute dorsally ( Fig. 37 ). Propodeum sometimes with median transverse ridge present posteriorly. Submarginal carina strongly produced as apical tooth above valvula, propodeal valvula elongate and free from submarginal carina posteriorly ( Fig. 38 ). Metasoma petiolate, both T1 and T2 petiolate (T2 petiolate basally). T2 and T3 usually with apical lamella ( Fig. 74 ). S1 abruptly widening near apex, forming a posterior crescentic sclerite, lateral margins of T1 closely approaching each other ventrally, usually fused. Mid tibia with two apical spurs. SMC2 basally truncate. Prestigma much shorter than pterostigma. Ƌ: F11 hook like, rounded apically ( Fig. 11 ); F10 shorter than previous ones; no cavity on the apical flagellomeres of antennae. Body length usually more than 20 mm.

Distribution. Mostly Neotropical, some in Ethiopian, Oriental, Palearctic and Nearctic Regions.

Figures

FIGURES 37 – 47. Posterior surface of propodeum. 37, 38, Zethus ceylonicus; 39, 40, Discoelius sp.; 41, Labus pusillus; 42, Pareumenes brevirostratus; 43, Stenodyneriellus wickwari. 44, Discoelius sp.; 45, Pareumenes brevirostratus; 46, Rhynchium carnaticum; 47, Anterhynchium mellyi. 44 – 47. Legs.

FIGURES 74 – 78. Metasoma, dorsal view. 74, Zethus ceylonicus; 75, Eumenes architectus; 76, Delta conoideum; 77, Oreumenoides edwardsii; 78, Coeleumenes i. impavidus.

FIGURES 1 – 12. Head, frontal view. 1, Eumenes architectus; 2, Phimenes flavopictus; 3, Labus pusillus; 4, Antepipona sp.; 5, Pareumenes brevirostratus; 6, Coeleumenes i. impavidus; 7, Anterhynchium mellyi; 8, Xenorhynchium nitidulum; 9, P. flavopictus; 10, Oreumenoides edwardsii; 11, Zethus ceylonicus; 12, Delta e. esuriens. 9 – 12. ♂