Zetheumenidion Bequaert 1926
Creators: name: Selis, Marco
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Vespidae
Zetheumenidion

description: Key to the species of Zetheumenidion Bequaert
1. Pronotal carina markedly depressed in the median third, where it is less than half as long as on lateral thirds; in dorsal view, anterior margin of pronotum markedly concave with anteriorly projecting lateral thirds (Fig. 14A). Mesepisternum coarsely punctured, interspaces mostly reduced to narrow sharp ridges (Fig. 14C).................... Z. pulchripenne (Cameron)
-. Pronotal carina of regular height for whole length, at most narrowly incised on median line; in dorsal view, anterior margin of pronotum straight or evenly concave, without anteriorly projecting lateral thirds (Fig. 14B). Mesepisternum variably punctured, but interspaces never reduced to sharp ridges (Figs. 14D–E)................................................... 2
2. Dorsal side of mesosoma forming an even surface from pronotum to dorsal faces of propodeum, without the slightest discontinuity between the sclerites; median furrow of propodeum very narrow and shallow in upper part, dorsal faces smoothly passing into each other (Fig. 14F). Male: outer face of hind femur markedly shagreened, shagreen visible at low magnification (Figs. 2D, 7C, 10D)................................................................................... 3
-. Dorsal side of mesosoma not forming an even surface, at least a weak but marked discontinuity between sclerites, either for scutellum raised above level of mesoscutum, convex metanotum, bulging dorsal faces of propodeum, or combinations of these; median furrow of propodeum wider and/or deeper in upper part, dorsal faces clearly separated by it (Fig. 14G). Male: outer face of hind femur smooth or with very fine shagreen visible at high magnification only (Figs. 1C, 3D, 4D, 5D, 6D, 8C, 9C).... 5
3. Lateral carinae of propodeum absent, transition between dorsal and lateral faces entirely rounded (Fig. 14M). Pronotum and mesoscutum strongly shiny, interspaces entirely smooth (Fig. 14H). Clypeus red in both sexes (Figs. 10B–C); on mesosoma, only pronotum with a narrow anterior ivory line (Fig. 10A); T2 reddish-orange at apex, without ivory band (Fig. 10E). Male: outer face of hind femur more finely and sparsely shagreened, distinctly shiny, with distinct deep punctures (Fig. 10D).................................................................................... Z. paeneplanum (Bequaert)
-. Lateral carinae of propodeum present and visible even if subtle, transition between dorsal and lateral faces angled (Figs. 14N–O). Pronotum and mesoscutum not so shiny, interspaces either with deep micropunctures or not sculpted but silky-shining (Figs. 14I–J). Clypeus marked with pale yellow in both sexes, almost entirely in male (female of Z. invertitum unknown) (Figs. 2B–C, 7B); on mesosoma, ivory markings at least on pronotum, tegula and parategula, commonly on scutellum and metanotum too (Figs. 2A, 7A); T2 with apical ivory band (Figs. 2E, 7D). Male: outer face of hind femur more coarsely and densely shagreened, matte, with very fine and barely visible punctures (Figs. 2D, 7C)...................................... 4
4. Lateral carinae of propodeum subtle and not projecting; lateral faces of propodeum concave, with distinct punctures (Fig. 14N). Interspaces on mesoscutum and scutellum narrower than puncture diameter, with deep micropunctures (Fig. 14I); posterior corners of propodeum with interspaces reduced to sharp ridges. Male: clypeus ivory-yellow with lateral black markings (Fig. 7B)......................................................................... Z. invertitum (Giordani Soika)
-. Lateral carinae of propodeum thick and strongly projecting, forming a hood above the lateral faces, which are flattened and finely striate (Fig. 14O). Interspaces on mesoscutum and scutellum about as wide as puncture diameter and silky shiny, without micropunctures (Fig. 14J); posterior corners of propodeum without narrow and sharp interspaces. Male: clypeus entirely ivory-yellow (Fig. 2B)............................................................ Z. celonitiforme (Giordani Soika)
5. Interspaces on pronotum and anterior half of mesoscutum wider than puncture diameter (Fig. 14K). T2 with deep punctures on whole surface; apical lamella of T2 strongly reflexed, about as high as two ocellar diameters and its apex exceeding height of preapical swelling (Fig. 6E)......................................................... Z. hessei (Giordani Soika)
-. Interspaces on pronotum and anterior half of mesoscutum shorter than puncture diameter (Fig. 14L). T2 with punctures disappearing in basal half; apical lamella of T2 flattened or weakly reflexed, at most as high as one ocellar diameter and its apex not exceeding height of preapical swelling (Figs. 1D, 3E, 4E, 5E, 8D, 9D).................................... 6
6. Propodeum with a well-developed subhorizontal face behind the metanotum, as long as the metanotum itself; in lateral view, the dorsal face is weakly oblique and then steeply curves into the posterior face (Fig. 14R). T 1 in lateral view abruptly expanded basally, forming a hump in basal third and then markedly narrowing to apex (Figs. 1D, 8D).......................... 7
-. Propodeum without a subhorizontal face, more or less convex but always sloping from base to apex (Fig. 14S). T 1 in lateral view evenly expanded basally, maintaining the same height and curvature for most of its length (Figs. 3E, 4E, 5E, 9D)..... 8
7. Lateral faces of propodeum deeply concave, forming a deep pit above valvula; propodeal valvula about as long as basally wide (Fig. 14P). T 1 in dorsal view not widened near base, width at level of spiracles about equal to apical width; dorsal face of T1 convex and evenly passing into lateral faces, without longitudinal furrow (Fig. 1A). Apical lamella of T2 less reflexed, in lateral view its apex not reaching height of preapical swelling (Fig. 1D)................................ Z. abruptum sp. nov.
-. Lateral faces of propodeum shallowly concave, not forming a pit above valvula; propodeal valvula longer than basally wide (Fig. 14Q). T 1 in dorsal view markedly widened near base, width at level of spiracles distinctly greater than apical width; dorsal face of T1 flattened and separated from lateral faces, with a longitudinal furrow at level of spiracles (Fig. 8A). Apical lamella of T2 more reflexed, in lateral view its apex reaching height of preapical swelling (Fig. 8D).............. Z. latum sp. nov.
8. Mesepisternum with dense small punctures (Fig. 14D). Mid-line of propodeum evenly weakly convex and sloping from base to apical orifice; posterolateral corners of propodeum not bulging above valvula in lateral view. Apical lamella of T2 not or barely reflexed, its apex placed well below level of preapical swelling (Figs. 3E, 5E)..................................... 9
-. Mesepisternum with large punctures (Fig. 14E). Mid-line of propodeum more strongly convex in dorsal half, not evenly sloping from base to apical orifice; posterolateral corners of propodeum distinctly bulging above valvula in lateral view. Apical lamella of T2 weakly but distinctly reflexed, forming a vertical part almost as high as one ocellar diameter and reaching height of preapical swelling (Figs. 4E, 9D)........................................................................ 10
9. Black and yellow, with some red markings on metasoma, sometimes small areas on mesosoma (Fig. 5A). Dorsal faces of propodeum with rounded smooth and shiny interspaces. Male: apical margin of clypeus subtruncate (Fig. 5B); hind femur weakly swollen on ventral face (Fig. 5D)........................................... Z. flavissimum Giordani Soika
-. Black and ferruginous-red, at most apex of T2 with orange-yellow tinge (Fig. 3A). Dorsal faces of propodeum with ridge-like microsculpted and matte interspaces. Male: apical margin of clypeus evenly emarginate (Fig. 3B); hind femur strongly swollen on ventral face (Fig. 3D)............................................................. Z. concinnoide sp. nov.
10. Clypeus about as long as wide; apical margin of clypeus subtruncate (Figs. 4B–C). Male: free apical part of clypeus about half as long as basal part (Fig. 4B); F1 proportionally robust, 2.3 × as long as wide............. Z. femoratum (von Schulthess)
-. Clypeus distinctly longer than wide; apical margin of clypeus distinctly emarginate (Fig. 9B). Male: free apical part of clypeus about 0.75 × as long as basal part (Fig. 9B); F1 proportionally slender, 2.6 × as long as wide. Female unknown................................................................................................ Z. minimum sp. nov.
description: Published as part of Selis, Marco, 2024, Revision of the Afrotropical genus Zetheumenidion Bequaert (Hymenoptera: Vespidae: Eumeninae), pp. 37-65 in Zootaxa 5406 (1) on pages 61-63, DOI: 10.11646/zootaxa.5406.1.2, http://zenodo.org/record/10611276