Key to the European Rhimphoctona species (modified after Horstmann, 1980)

1. Females............................................................................................ 2

- Males (no R. longicauda males were studied)............................................................. 11

2. Hind coxa red, at most brownish basally................................................................... 3

- Hind coxa black, at most red apically (in R. teredo).......................................................... 4

3. Fore wing more than 10 mm long. Temples long and widened (Fig. 1. 1). Mesopleuron densely and strongly punctate (Fig. 2. 1). Propodeum with area superomedia rugulose (Fig. 4. 1). Ovipositor is about 1.5 × the length of the hind tibia............................................................................................... R. grandis (Fonscolombe)

- Fore wing less than 10 mm long. Temples long and parallel (Fig. 1. 2). Mesopleuron more weakly punctate (Fig. 2. 2). Propo- deum with area superomedia granulate (Fig. 4. 2). Ovipositor is about as long as the length of the hind tibia................................................................................................ R. rufocoxalis (Clément)

4. Mesoscutum weakly sculptured (Fig. 5. 1). Temples long and widened (Fig. 1. 3). Mesopleuron sparsely punctate. Propodeum with costula present (Fig. 4. 3). Ovipositor is about 1.4–1.5 × the length of the hind tibia............... R. lucida (Clément)

- Mesoscutum more strongly sculptured (Fig. 5. 2)............................................................ 5

5. Propodeum with costula absent or indistinct (e.g. Figs 4. 4, 5). Temples long...................................... 6

- Propodeum with costula distinct and strong (e.g. Figs 4. 1, 3). Temples short...................................... 8

6. Ovipositor is about 0.5–0.6(0.9) × the length of the hind tibia. Hind femur brown. Temples parallel. Female clypeus and malar space around the mandibular base sometimes red......................................... R. obscuripes (Holmgren)

- If the female clypeus and malar space around the mandibular base red, than the ovipositor is about 1.3 × the length of the hind tibia. Hind femur at most brownish apically (in R. teredo)......................................................7

7. Ovipositor is about 1.3–1.5 × the length of the hind tibia. Temples long and widened (Fig. 1. 4). Female clypeus and malar space around the mandibular base often red. Mesopleuron densely punctate, speculum granulate (Fig. 2. 3).............................................................................................. R. xoridiformis (Holmgren)

- Ovipositor is about 0.8 × the length of the hind tibia.Temples long and parallel (Fig. 1. 5). Mesopleuron more strongly punctate, speculum distally unsculptured (Fig. 2. 4)..................................................... R. teredo (Hartig)

8. Propodeum with area basalis wide distally and area superomedia wider than area basalis (Fig. 4. 8). Mesopleuron sparsely punctuate (Fig. 3. 1). Ovipositor is about 1.5 × the length of the hind tibia..................... R. longicauda Horstmann

- Propodeum with area basalis narrow distally (Figs 4. 7, 10, 12). Mesopleuron densely punctate (Figs 3. 2–4)............. 9

9. Propodeum with area superomedia wider than area basalis (Fig. 4. 7). Ovipositor is about 1.4 × the length of the hind tibia.................................................................................... R. melanura (Holmgren)

- Propropodeum with area superomedia as wide as area basalis (Figs 4. 9, 12)..................................... 10

10. Propodeum with area superomedia closed with more or less distinct carinae, costula sometimes indistinct distally (Fig. 4. 9). Ovipositor is about 1.3–1.7 × the length of the hind tibia.............................. R. megacephalus (Gravenhorst)

- Propodeum with area superomedia partly enclosed distally or/and laterally, costula distinct distally (Fig. 4. 12). Ovipositor is about 1.1–1.3 × the length of the hind tibia........................................... R. pectoralis (Kriechbaumer)

11. Hind coxa red. Propodeum with costula distinct............................................................ 12

- Hind coxa black, at most yellow apically. Propodeum with costula sometimes indistinct or absent.................... 14

12. Face black...................................................................... R. grandis (Fonscolombe)

- Face yellow (Fig. 5. 3)................................................................................ 13

13. Mesopleuron black................................................................. R. rufocoxalis (Clément)

- Mesopleuron yellow ventrally (Fig. 5. 3)............................................. R. pectoralis (Kriechbaumer)

14. Face black. Mesoscutum weakly sculptured. Temples long and widened. Propodeum with costula distinct..................................................................................................... R. lucida (Clément)

- Face yellow........................................................................................ 15

15. Propodeum with costula distinct at least proximally. Temples parallel.......................................... 16

- Propodeum with costula indistinct. Temples from parallel to widened.......................................... 17

16. Mesopleuron yellow ventrally. Hind trochanter yellow. Yellow coloration of temples wide......... R. melanura (Holmgren)

- Mesopleuron black. Hind trochanter red. Yellow coloration of temples narrow............. R. megacephalus (Gravenhorst)

17. Hind femur brown. Face yellow with a central apical black spot. Temples parallel............... R. obscuripes (Holmgren)

- Hind femur red, at most brownish apically................................................................ 18

18. Temples widened. Propodeum with longitudinal carinae partly indistinct. Face yellow with a central vertical black line.................................................................................... R. xoridiformis (Holmgren)

- Temples parallel. Propodeum with longitudinal carinae distinct. Face yellow with a central apical black spot.................................................................................................... R. teredo (Hartig)