Zethus (Zethusculus) de Saussure, 1855

Lopes, Rogerio Botion, Carpenter, James M. & Noll, Fernando Barabosa, 2021, Cladistic analysis of Zethus Fabricius, 1804 (Hymenoptera, Vespidae): a new subgeneric classification, Journal of Hymenoptera Research 82, pp. 253-283 : 253

Zethus (Zethusculus) de Saussure, 1855

Fig. 12

Zethusculus de Saussure, 1855: 118 (division of genus Zethus ); 1875: 18 (division of Zethus ).

Zethus jurinei Type species: Zethus jurinei de Saussure.

Zethucculus Howes, 1917: 407 (misspelling).

Zethus (Zethusculus) Bohart & Stange, 1965: 20 (dendrogram), 25 (key to subgenera), 125 (subgenus of Zethus , key to species), 202 (figs). Lopes and Noll 2018 (paraphyletic).

Description.

Interantennal longitudinal and transversal carinas absent. Male flagellum rolled (Fig. 12D ). Female clypeus microstriate (Fig. 12B ), short and without apical teeth. Male mandible 3-toothed. Galea short. Labial palpi 4-segmented with first palpomere curved. Occipital carina ventrally complete or as small branch. Vertex usually raised (flat only in the imperfectus group). Genal margin mostly evenly convex (sinuous in the imperfectus group). Pronotal carina lamellar with lateral portion strongly sinuous. Pre-tegular carina incomplete. Welts and notalulices absent. Tegula with outer margin usually angled, raised except for medial interruption (Fig. 12C ). Epicnemial carina complete. Mesepimeron without carina. Mid tibia with one apical spur. Metanotum anteriorly margined with lateral carina extending at most to anterior half of the sclerite. Spines in posterior tibia scattered. Apical angle of marginal cell variable. Dorsal aperture of propodeum only present in imperfectus group. Propodeum with lateral carinas and without submedian and sublateral carinas. Apical lamella of propodeum only present in imperfectus group. T1 with short stem and medium expansion. S1 with elliptical anterior margin. S2 with apicall lamellae. T3 with apical lamella only in imperfectus group. S3 without lamellae only in Zethus mexicanus group. S5 and 6 without carinas. Anterior margin of ventral lobe of aedeagus reflexed outward. Cuspis with apical tuft.

Observations.

While Lopes and Noll (2018) recovered this subgenus as paraphyletic, the results here present support the wider analysis of the group (Golfetti et al. 2020) where it is recovered as monophyletic.

Distribution.

Nearctic and Neotropical.

Included species-groups.

Zethus arietis , Zethus imperfectus , Zethus mexicanus .

Included species.

27.

Nomen dubium

These taxa of doubtful application lack evidence that allows a proper affiliation to species-groups or subgenera, thus considering them incertae sedis as well. Three of the taxa are already cited in Bohart and Stange (1965): Z. assimilis ( Brèthes), Z. holmbergii Brèthes and Z. medius Brèthes. Three species are added to this list: Z. didymogastra Spinola, Z. rufipes Fox and Z. scandens Zavattari.

Zethus didymogastra Spinola, 1841 - After its description, de Saussure (1852) synonymized it under Z. binodis Fabricius, only to go back and validate Z. didymogastra again after two decades (de Saussure, 1875). The last mention of this species was by Cameron (1912) when he synonymized it once again also under Z. binodis . Nevertheless, the taxonomic catalog of Z. binodis in Bohart and Stange (1965) does not bring the synonym nor is the species brought up anywhere else in their study.

Zethus rufipes Fox, 1899 - This taxon makes a rather curious case, where Bohart and Stange (1962) desginated a lectotype, but never mentioned it in their great revision of 1965. The fact that this species was omitted in Bohart and Stange (1965) was noted by Carpenter and Vecht (1991).

Zethus scandens Zavattari, 1913 - This species was described by Zavattari and only again cited by Rasmussen and Asenjo’s (2009) catalog for Peruvian fauna. No remarks or lists were made by any other authors, not even Bohart and Stange (1965).

Figures

Figure 12. Synapomorphic characters of Zethus (Zethusculus) A habitus of Z. jurinei B close-up of female clypeus of Z. mexicanus C tegula of Z. mexicanus; arrowheads indicate length of interruprion on raised margin D male flagellum of Z. mexicanus. Scale bars: 1.0 mm.