Key to the species of Euodynerus occurring in Europe and the Maghreb

1. S2 step-like in lateral view, with a basal vertical face sharply delimited by transverse ridge which is strongly projecting in the middle (Fig. 15A); surface of S2 shallowly but distinctly depressed just behind transverse ridge (Fig. 15A). Propodeum without dorsal carinae (Fig. 15F). Vestiture of head, mesosoma and anterior part of metasoma made of long and wavy setae, reaching up to three ocellar diameters in length (Fig. 15J)............................................................. 2

- Characters not combined as above. S2 usually evenly convex in lateral view and with a basal furrow in the middle (Figs 15B, C, E); if step-like, then basal transverse ridge broadly interrupted in the middle by longitudinal furrow and not projecting as above (Fig. 15D); surface of S2 usually not depressed in lateral view (depressed as above only in E. caspicus). Propodeal carinae and vestiture variable, but never combined as above (e.g. if propodeum without dorsal carinae, then vestiture not made of long and wavy setae) (Figs 15G–I, K–O).......................................................................... 3

2. Disc of clypeus entirely flattened and not depressed above apex; apical margin wider than interantennal space, subtruncate in female and deeply emarginate in male (Figs 4C–E). Punctures on mesosoma finer and denser and with densely micropunctate interspaces, giving matte appearance. Scutellum with subtriangular lateral spots (absent in ssp. puniceus), metanotum entirely black and metasoma with at least five tergites with apical yellow band (only two with ferruginous band in ssp. puniceus); wings with orange tinge in basal half and slightly infuscate apical half (Figs 4A, B). Female: cephalic foveae placed in barely differentiated circular area, narrower than ocellar triangle (cf. Fig. 15X).................. E. (E.) bidentatus (Lepeletier)

- Disc of clypeus convex, with small shallowly depressed area above apex; apical margin narrower than interantennal space, shallowly but distinctly emarginate (Fig. 11D). Punctures on mesosoma larger and sparser and with scattered micropunctures in interspaces, giving shiny appearance. Scutellum entirely black, metanotum with wide yellow band covering its upper half and metasoma with only three (♀) or four (♂) apical bands; wings entirely hyaline with subtle grayish-brown tinge (Fig. 11A). Female: cephalic foveae placed in clearly differentiated elliptical area, wider than ocellar triangle (cf. Figs 15U–W)............................................................................. E. (P.) bidentiformis (Giordani Soika)

3. Dorsal carinae of propodeum forming sharp lamellar tooth on medial end, adjacent to disc of metanotum (Fig. 15G). Metanotum with posterior margin of dorsal face finely denticulate and evenly rounded, margin complete or at most narrowly interrupted (Fig. 15P). Male: apical segment of mid and hind tarsi variably darkened but always contrasting with yellowish preceding segments, and variably widened (Figs 15R, S). Female: cephalic foveae placed in clearly differentiated elliptical area, wider than ocellar triangle (Figs 15U–W)....................................................................... 4

- Dorsal carinae of propodeum variable, from absent (Fig. 15H) to complete but not forming distinct tooth and widely separated from metanotum (Fig. 15I). Metanotum with posterior margin of dorsal face coarsely denticulate and laterally raised, margin usually depressed and interrupted in middle (Fig. 15Q). Male: tarsi of all legs entirely ferruginous-yellow and not widened, apical segment not contrasting with preceding ones (Fig. 15T). Female: cephalic foveae placed in barely differentiated circular area, narrower than ocellar triangle (Fig. 15X), or mixed with surrounding punctures (Fig. 15Y)....................... 8

4. S 2 in lateral view abruptly convex basally, almost forming short vertical face separated from rest of sternite by shallow fold narrowly interrupted in middle (Fig. 15B).................................................................. 5

- S 2 in lateral view evenly convex from base to apex, basal third of sternite somewhat depressed in middle (Fig. 15C)...... 6

5. Gena and vertex strongly developed, in dorsal view gena much longer than dorsal lobe of eye (Fig. 15V). Apical lamella of T1 shorter, almost linear in middle and barely reaching one puncture diameter on sides; punctures of T2 becoming sparser apically (Figs 11B, C). Vestiture of head and mesosoma, including base of legs, longer and wavier, reaching up to three ocellar diameters in length (cf. Fig. 15J). Light markings extensive and bright yellow, with at least four bands on tergites (Figs 11B, C)............................................................................. E. (P.) bidentoides (Giordani Soika)

- Gena and vertex normally developed, in dorsal view gena as long as dorsal lobe of eye (Fig. 15W). Apical lamella of T1 longer, well visible in middle and exceeding one puncture diameter on sides; punctures of T2 forming denser preapical band (Figs 13K, M). Vestiture of head and mesosoma shorter and stiffer, not reaching two ocellar diameters in length (cf. Fig. 15L). Light markings reduced and orange-red, with only three bands on tergites (third band laterally abbreviated) (Figs 15K, M).............................................................................. E. (P.) rubrosignatus Gusenleitner

6. Vestiture of mesosoma long and wavy, exceeding two ocellar diameters in length (Fig. 15K)................................................................................................... E. (P.) quadrifasciatus (Fabricius)

- Vestiture of mesosoma short and straight, brush-like, not exceeding one ocellar diameter in length (Fig. 15L)............ 7

7. Clypeus more finely and sparsely punctate, interspaces on disc always exceeding puncture diameter in length (Figs 12D–G). Pronotal carina weakly lamellate. Propodeum always entirely black, tibiae usually marked with black at least on inner face. Male: clypeus more convex basally than apically, with long free apical part and clearly emarginate apical margin (Figs 12D, E); mandible with basalmost tooth similar to other teeth, outer surface mostly black with yellow basal triangle (Fig. 16A); apical segment of mid and hind tarsi black and distinctly widened (Fig. 15R)......................... E. (P.) notatus (Jurine)

- Clypeus more coarsely and densely punctate, interspaces on disc mostly not exceeding puncture diameter in length (Figs 12J, K). Pronotal carina strongly lamellate. Propodeum usually largely marked with yellow (yellow markings reduced in northeastern populations), tibiae entirely yellow with ferruginous inner face. Male: clypeus evenly convex from base to apex, with very short free apical part and subtruncate apical margin (Fig. 12J); mandible with basalmost tooth larger and perpendicular to axis of other teeth, outer surface almost entirely yellow (Fig. 16B); apical segment of mid and hind tarsi reddish-brown and not markedly widened (Fig. 15S)............................................... E. (P.) posticus (Herrich-Schaeffer)

8. S2 step-like in lateral view, with basal vertical face sharply delimited by bulging transverse ridge widely interrupted in the middle; surface of S2 shallowly but distinctly depressed just behind transverse ridge (Fig. 15D). Tegula with scattered deep punctures on whole surface and strongly pointed posterior lobe (Fig. 16C). Posterior horizontal face of T1 entirely orangeyellow, rarely with barely visible median dark line (Figs 4F, G)........................... E. (E.) caspicus (Morawitz)

- S2 more or less evenly convex in lateral view, without basal transverse ridge; surface of S2 not depressed (Fig. 15E). Tegula impunctate or with coarser punctures and less pointed posterior lobe (Figs 16D–G). Posterior horizontal face of T1 at least with well-developed longitudinal black band, usually with semicircular or pentagonal large black area basally................ 9

9. Posterior lobe of tegula with dense coarse punctures, usually deep but still well-evident even when shallow (Figs 16D, E). Dorsal side of mesosoma with very sparse and fine dust-like pubescence, almost bare (Fig. 15M). Clypeus with coarse and dense longitudinal striae in female, with finer striae and elongate punctures in male (Figs 6I–O; 8D–F)................ 10

- Posterior lobe of tegula smooth or with few scattered fine punctures, visible only under incident light (Figs 16F, G). Vestiture of dorsal side of mesosoma variable, dust-like and sparse (cf. Fig. 15M), long and brush-like (Fig. 15N) or with scattered bent setae (Fig. 15O). Clypeus with fine and sparse longitudinal striae intermixed with punctures in female (in E. disconotatus with some scattered coarser striae), without striae and with rounded punctures in male (Figs 5D–H; 7E–H; 7L–O; 8J–M; 9D–H, L, M)................................................................................................ 11

10. Apical margin of clypeus subtruncate (Figs 8D–F). Outer margin of tegula distinctly bent in posterior half, becoming almost perpendicular to longitudinal axis of body (Fig. 16D). Apical translucent margin of T2 longer and shallowly reflexed (Fig. 16H). Female: clypeus as wide as long (Figs 8E, F); F1 and part of F2 usually reddish; ventral side of metasoma largely yellow with reduced black markings...................................................... E. (E.) hellenicus Blüthgen

- Apical margin of clypeus shallowly but distinctly emarginate (Figs 6I–O). Outer margin of tegula evenly rounded in posterior half (Fig. 16E). Apical translucent margin of T2 very narrow and linear, barely developed (Fig. 16I) (rarely longer and shallowly reflexed in male specimens). Female: clypeus longer than wide (Figs 6K–O); flagellum entirely black dorsally; ventral side of metasoma largely black with lateral yellow spots........................................... E. (E.) dantici (Rossi)

11. Dorsal side of mesosoma with dense erect setae, brush-like (Fig. 15N).......................................... 12

- Dorsal side of mesosoma with dust-like pubescence (cf. Fig. 15M), only in E. semisaecularis with sparse apically bent erect setae (Fig. 15O)..................................................................................... 13

12. Punctures on mesepisternum arranged in longitudinal series, with interspaces forming irregular parallel striae. Male: apical margin of clypeus with deep semi-circular emargination, apical teeth acute and their distance equal to interantennal space (Fig. 9L); hind femur angularly expanded on base of hind margin (Fig. 16J). Female: apical margin of clypeus deeply emarginate; clypeus black or with small markings on basal corners (Fig. 9M)........................... E. (E.) velutinus Blüthgen

- Punctures on mesepisternum not arranged in series, interspaces forming irregular reticulation. Male: apical margin of clypeus shallowly emarginate, apical teeth more or less right-angled and their distance wider than interantennal space (Figs 5D, E); hind femur not expanded, hind margin entirely straight (Fig. 16K). Female: apical margin of clypeus subtruncate; clypeus with broad basal yellow markings to almost entirely yellow (Figs 15F–H)............................ E. (E.) curictensis Blüthgen

13. Tegula narrower and with more or less evenly curved outer margin, with few scattered fine punctures (Fig. 16F). Male: S6 and S7 with erect setae, either long or short (Figs 16L, M). Female: cephalic foveae placed in differentiated area with shiny and smooth surface (Fig. 15X)............................................................................. 14

- Tegula wider and with outer margin more strongly rounded in posterior half, almost smooth (Fig. 16G). Male: S6 and S7 with dust-like pubescence, some very short oblique setae at apex only (Fig. 16N). Female: cephalic foveae not placed in differentiated area, mixed with surrounding punctures (Fig. 15Y).............................................. 15

14. Dorsal side of mesosoma almost bare, with very sparse dust-like pubescence (cf. Fig. 15M). Male: clypeus longer than wide, with deep and dense punctures (Fig. 7L); S6 and S7 with long erect setae on whole surface (Fig. 16L). Female: face with short pubescence around antennal insertions not reaching bottom of ocular sinus.............. E. (E.) fastidiosus (de Saussure)

- Dorsal side of mesosoma with sparse apically bent setae in addition to dust-like pubescence (Fig. 15O). Male: clypeus about as long as wide, with shallow sparse punctures (Figs 8J, K); S6 and S7 with short setae on apical half only (Fig. 16M). Female: face with long dense pubescence in whole lower half and reaching bottom of ocular sinus................................................................................................... E. (E.) semisaecularis (Dalla Torre)

15. Mesoscutum with subquadrate yellow marking in front of scutellum (Fig. 7C), usually absent in males (Fig. 7B) (present in Eastern populations, Fig. 7A) and rarely reduced in females (Fig. 7D); scutellum usually with two separate subtriangular spots (Figs 7B–D) (broad band in populations from Asia, Fig. 7A); metanotum with broad yellow band covering dorsal half (Figs 7A–D). Male: clypeus as long as wide with apical margin as wide as interantennal distance, surface with sparse but clearly visible punctures (Fig. 7E). Female: clypeus coarsely punctate and with some longitudinal striae, apical carinae mixed with coarse sculpture and not well-evident (Figs 7F–H)............................... E. (E.) disconotatus (Lichtenstein)

- Mesoscutum entirely black (Figs 9A–C); scutellum usually with wide band covering most of its surface (Figs 9A, B) (reduced to spots or absent in populations from the Levant, which have red markings, Fig. 9C); metanotum at most with irregular band along transverse carina (Figs 9A–C). Male: clypeus longer than wide with apical margin narrower than interantennal distance, surface microsculpted with very fine punctures visible only at high magnification (Fig. 9D). Female: clypeus finely and sparsely punctate, at most with scattered microstriation between punctures, apical carinae not mixed with sculpture and well visible (Figs 9E–H)......................................................... E. (E.) variegatus (Fabricius)