Zethus ( Zethoides ) nolli Lopes, 2025

Lopes, Rogério Botion & Hermes, Marcel Gustavo, 2025, The Neotropical Zethus biglumis species-group (Hymenoptera, Vespidae, Zethinae): description of three new species, with notes on the evolution of the group, Zootaxa 5701 (2), pp. 122-130 : 127-128

Zethus ( Zethoides) nolli Lopes , sp. nov.

Zethus ( Zethoides) rugosiceps : Lopes & Noll 2015: 2–3 (figures, new record for São Paulo) [misidentification]; 2018: 106 (examined material), 117 (figure) [misidentification].

Type material. Holotype female: “ Sales, SP [ São Paulo], Brasil \ 24/X/07 \ Noll col. Malaise” [ DZSJRPHymenoptera].

Diagnosis. The species is unique among the group due to the combination of presenting a subapical reflexed tooth on the mandible and the barely projected humeral angle.

Description of female. Coloration. Black with the following yellow markings: ventral surfaces of antennal escape and pedicel; a pair of wide spots above antennal sockets; spot on ocular sinus; narrow band along base of pronotal carina; anterior and posterior spots on tegula; parategula; pair of narrow lateral spots on scutellum; subapical bands on T1 to T3 and S2 and S3. Outer surface of mid tibia creamy yellow. Testaceous-colored regions: tegula; fore tibia except for posterior surface; fore tarsus entirely; mid tarsomeres III to V; hind tarsomeres IV and V. Mandibles apically reddish, except for black teeth. Fore wings hyaline, light brown, with costa darker and dark brown venation.

Structure. Clypeal apex ridged and biconcave, with well-developed teeth. Mandible 4-toothed and with an additional inflexed tooth between teeth III and IV. Genal margin sinuous. Pronotal carina high as a transluscent lamella on dorsum and short and sinuous laterally. Humerus rounded with slightly projected angles. Outer margin of tegula straight, with the posterior portion strongly bowed out, with margin nearly transversal to body axis. Outer margin of tegula entirely raised. Scutellum convex. Metanotum bent in profile with posterior surface shorter than dorsal surface. Mid tibia with two apical spurs. Socket of hind coxa with reflexed inner margin. Spines on outer margin of mid and hind tibia, scattered on the former and in a line on the latter. Posterior surface of propodeum weakly concave. Dorsal propodeal aperture present, as slit without dorsal margin. Apical propodeal lamella triangular, dark in color with lighter tip. T1 regularly convex in profile view, with greatest width near mid-length in dorsal view. S1 flat. T2 lamella longer laterally than medially. S2 regularly convex. T3 lamella tripartite. S3 lamella reduced with large median lobe.

Sculpture. Clypeus with dense macropuncatation and obsolete micropunctation. Transversal and longitudinal interantennal carinas blunt.Head, dorsum of pronotum, scutum and scutellum with dense and shallow macropunctures intercalated by dense micropunctation. Occasionally, macropunctures are coalescent on pronotum and anterior portion of mesoscutum. Notauli feebly visible on posterior fourth. Welts faintly indicated. Discoid puncture present on top of a smooth tubercle. Mesopleura without dorsal suture. Metanotum with a median thin tooth. Lateral carina of metanotum lamellar extending the entire length of the sclerite without curving inwards. Propodeum with complete lateral carina. Submedian carinas interrupted mid-way. Punctation of propodeal concavity hidden by dense pilosity. Few strong short oblique striae branch laterally from submedian and lateral propodeal carinas. T1 with sub-basal carina well-developed. T1 with moderate to dense macropunctation interspaced by smooth areas. T2 and T3 with very dense micropunctation that obscures any macropuncture and is interrupted subapically, where a smooth band is formed. S2 mostly smooth with sparse small macropunctures, laterally taken over by very dense micropunctation. (S3 punctation not observable, blocked by S2). T4 densely micropunctate. (T5 blocked by T4). T6 and S4 to S6 shagreened with apical very shallow and small punctation.

Pilosity. Overall covered by long erect golden setae. Clypeus also with whitish long and appressed pilosity, especially on lateral and dorsal portions. Dorsum of mesosoma also with short appressed golden pilosity. Erect setae denser on propodeum. T2 with dense golden tomentum than becomes gradually sparser on following terga until completely absent on T6. Erect setae on T4 to T6 and S4 to S6 limited to apical portion.

Fore wing length 9.4 mm.

Male. Unknown.

Distribution. Brazil ( São Paulo).

Etymology. The specific epithet is an homage to Fernando Barbosa Noll, collector of the specimen and great contributor to the study of aculeate wasps.