Key to species of Probles occurring in Mexico

1. Propodeum with long basal keel (sometimes obliterated) which is 0.8–1.1× as long as apical area (Figs 5, 45, 46, 51)...... 2

- Propodeum with basal area or short (0.6× or less) basal keel................................................... 4

2. Second tergite 1.5–1.8× as long as anteriorly broad. First tergite with upper margin evenly and strongly convex in lateral view (Fig. 44). Ovipositor short and robust (Fig. 43), with sheath 0.8–1.1× as long as first tergite....... 7. P. megasoma sp. nov.

- Second tergite twice as long as anteriorly broad (Fig. 54). First tergite, in lateral view, with upper margin straight or weakly convex in basal 0.7 and strongly convex in apical 0.3 (Figs 4, 53). Ovipositor very long and slender (Figs 7, 55), with sheath 2.4–3.0× as long as first tergite.......................................................................... 3

3. Notaulus with distinct wrinkle on anterolateral margin of mesoscutum. Gena granulate. Ovipositor evenly upcurved, with small dorsal subapical notch (Fig. 7)......................................................... 1. P. alejandroi sp. nov.

- Notaulus completely absent. Gena smooth. Ovipositor somewhat stronger upcurved at apex, with shallow dorsal subapical depression (Fig. 55)............................................................... 8. P. miquihuana sp. nov.

4. Mandible very slender with upper tooth exceptionally long, 3.0–4.0× longer than the lower (Fig. 11). First metasomal tergite very slender, 3.8× as long as posteriorly broad, entirely smooth, with small glymma in apical 0.65 joining by fine furrow to ventral part of postpetiole (Figs 8, 67). Flagellum with 15–16 flagellomeres (Figs 12, 68)............................ 5

- Mandible less slender, with upper tooth at most twice as long as the lower. First metasomal tergite usually shorter, often striate laterally and dorsally, sometimes with large glymma. Number of flagellomeres varies from 14 to 24.................... 6

5. Fore wing with second recurrent vein (2m-cu) interstitial (Fig. 8). Malar space as long as basal mandibular width. Propodeal spiracle separated from pleural carina by 1.5× diameter of spiracle (Fig. 13). Ovipositor sheath as long as first tergite (Fig. 8).............................................................................. 2. P. belokobylskii sp. nov.

- Fore wing with second recurrent vein (2m-cu) distinctly postfurcal. Malar space half as long as basal mandibular width. Propodeal spiracle separated from pleural carina by half diameter of spiracle (Fig. 69). Ovipositor sheath 1.8× as long as first tergite (Fig. 67).......................................................................... 11. P. xalapana sp. nov.

6. Second tergite 1.1–1.3× as long as anteriorly broad (Fig. 78)................................................... 7

- Second tergite 1.4–2.0× as long as anteriorly broad.......................................................... 8

7. Clypeus unusually small, 0.75× as broad as face (Fig. 17). Antennal flagellum slender, filiform, with 16 flagellomeres; subapical flagellomeres distinctly elongated. Mandible strongly tapered, 2.5× broader basally than at level of teeth (Fig. 17). Propodeum with basal area (Fig. 18). Ovipositor sheath twice as long as first tergite.................... 3. P. clypeola sp. nov.

- Clypeus not unusually small, about as broad as face. Antennal flagellum robust, distinctly clavate, with 21–24 flagellomeres; subapical flagellomeres transverse (Fig. 73). Mandible weakly tapered, 1.3–1.4× broader basally than at level of teeth. Propodeum with basal keel which is sometimes indistinct (Fig. 74). Ovipositor sheath 1.1–1.3× as long as first tergite (Fig. 76)................................................................................ 12. P. zacapoaxtlana sp. nov.

8. Flagellum with 14–16 flagellomeres (Figs 20, 57). Notaulus absent. Head and mesosoma almost entirely polished. Very small species with body length 2.4–2.7 mm ..................................................................... 9

- Flagellum with 20–23 flagellomeres. Notaulus usually with distinct wrinkle. Head and mesosoma predominantly granulate, sometimes partly smooth on gena and mesopleuron. Body usually larger........................................ 10

9. Propodeum with basal area 1.1× as long as apical area (Fig. 24). Ovipositor with deep dorsal subapical notch (Fig. 25); sheath 4.5× as long as first tergite............................................................ 4. P. contrerasi sp. nov.

- Propodeum with basal area shorter, 0.6× as long as apical area (Fig. 60). Ovipositor evenly pointed from base to apex, without dorsal subapical notch (Fig. 61); sheath 1.2× as long as first tergite................................ 9. P. picus sp. nov.

10. Head, in dorsal view, weakly constricted behind eyes, with gena 0.85–0.9× as long as eye width (Fig. 64). Gena granulate. Eyes with short setae.................................................................... 10. P. spectabilis sp. nov.

- Head, in dorsal view, strongly constricted behind eyes, with gena 0.55–0.65× as long as eye width (Figs 27, 35). Gena polished. Eyes glabrous....................................................................................... 11

11. Mandible with upper tooth distinctly longer than the lower (about 2.0×). Second flagellomere 1.8–2.0× as long as broad (Fig. 26). Propodeum with narrow indistinct basal area which is 0.4–0.5× as long as apical area (Fig. 29). Propodeal spiracle separated from pleural carina by 1.5× diameter of spiracle (Fig. 28). Ovipositor sheath about 1.5× as long as first tergite.......................................................................................... 5. P. juanitae sp. nov.

- Mandible with upper tooth just slightly longer than the lower (1.5× or less). Second flagellomere about 2.5× as long as broad (Fig. 34). Propodeum with broad basal area which is 0.8–1.0× as long as apical area (Figs 37, 38). Propodeal spiracle separated from pleural carina by 0.5–1.0× diameter of spiracle. Ovipositor sheath 2.0–2.8× as long as first tergite (Fig. 32)............................................................................................... 6. P. lunai sp. nov.