Key for identification of female aphidiines attacking aphids that feed on alfalfa in Europe

1 Fore wing venation with eight cells; fore wing 3RSb reaching the wing margin (Fig. 1); mummy black (Fig. 21).......................................................................................... Ephedrus plagiator (Nees)

- Fore wing venation with fewer than eight cells; fore wing r& RS vein (Figs 2–9) or RS vein (Figs.10–20) not reaching the wing margin; mummy not black (Figs 22, 23).................................................................... 2

2 Fore wing RS + M vein present (Figs 2–5); pupation under aphid’s empty skin (mummy) (Fig. 22)..................... 3

- Fore wing RS + M vein absent (Figs 6–20); pupation inside mummy (Fig. 23)..................................... 6

3 Flagellomere 1 yellow and elongated; m-cu in fore wing absent or reduced (present only short part of m-cu vein) (Fig. 2); propodeum sparsely pubescent (Fig. 24).................................................. Praon exsoletum (Nees)

- Flagellomere 1 completely brown or with a basal yellowish ring, not elongated; fore wing with well-developed m-cu vein (Figs 3–5); propodeum densely pubescent (Figs 25, 26)........................................................... 4

4 Lateral lobes of mesonotum sparsely pubescent (Fig. 27); antenna 15–16-segmented; dorsal outline of ovipositor sheath straight.......................................................................... Praon abjectum (Haliday)

- Lateral lobes of mesonotum densely pubescent (Figs 28, 29); antenna with more than 16 segments; dorsal outline of ovipositor sheath concave........................................................................................ 5

5 Antenna 17–18 (19)-segmented; fore wing m-cu vein coloured throughout (Fig. 4); face moderately setaceous.............

................................................................................. Praon volucre (Haliday) - Antenna 20–21 segmented; fore wing m-cu vein colourless throughout (Fig. 5); face densely setaceous................................................................................................. Praon barbatum (Mackauer)

6 Fore wing M, m-cu, and r-m veins absent (Figs 6–9).......................................................... 7

- Fore wing M and m-cu veins united forming M & m-cu vein, at least partly developed under r-m vein; r-m vein coloured or colourless (Figs 10–20)............................................................................... 10

7 Hypopygium without prongs (Fig. 30).................................................. Lipolexis gracilis Förster

- Hypopygium with two prongs (Figs 31–33)................................................................. 8

8 Petiole with primary tubercles only (Fig. 34).......................................... Trioxys complanatus Quilis

- Petiole with primary and secondary tubercles (Figs 35, 36)..................................................... 9

9 Distance between primary and secondary tubercles shorter than width at spiracles (Fig. 35); petiole and distal tergites dark- brown...................................................................... Binodoxys acalephae (Marshall)

- Distance between primary and secondary tubercles longer than width at spiracles (Fig. 36); petiole dark-brown to yellow................................................................................ Binodoxys angelicae (Haliday)

10 Fore wing M & m-cu vein only partly developed under r-m vein (Figs 10–13).................................... 11

- Fore wing M & m-cu vein completely developed (Figs 14–20)................................................. 14

11 Fore wing vein R1 shorter than stigma (Figs 10, 11); labial palps with two palpomeres.............................. 12

- Fore wing vein R1 longer than stigma (Figs 12, 13); labial palps with one palpomere............................... 13

12 Flagellomere 1 with 1-2 longitudinal placodes; fore wing stigma 2.90–3.20 times as long as wide (Fig. 10); setae on distal mar- gin of fore wing equal to those on surface (Fig. 10)........................ Lysiphlebus orientalis Starý and Rakhshani

- Flagellomere 1 with 4–6 longitudinal placodes; fore wing stigma 2.50–2.80 times as long as wide (Fig. 11); setae on distal margin of fore wing longer than those on surface (Fig. 11)........................... Lysiphlebus testaceipes (Cresson)

13 Setae on distal margin of fore wing equal to those on surface (Fig. 12)................... Lysiphlebus fabarum (Marshall)

- Setae on distal margin of fore wing longer than those on surface (Fig. 13).......... Lysiphlebus confusus Tremblay & Eady

14 Ovipositor sheath widened ventrally, ploughshare-shaped (Fig. 45)....................... Monoctonus nervosus Haliday

- Ovipositor sheath not widened ventrally, short............................................................. 15

15 Anterolateral area of petiole rugose (Fig. 37)............................................... Aphidius ervi Haliday

- Anterolateral area of petiole costate (Figs 38, 39) or costulate (Figs 40–42)...................................... 16

16 Anterolateral area of petiole costate (Figs 38, 39)........................................................... 17

- Anterolateral area of petiole costulate (Figs 40–42).......................................................... 18

17 Antenna (16) 17-segmented; fore wing stigma 1.6–2.0 times as long as fore wing R1 vein (Fig. 15); anterolateral area of peti- ole sharply costated (Fig. 38)......................................................... Aphidius avenae Haliday

- Antenna 15 (16)-segmented; fore wing R1 vein subequal to stigma (stigma 1.1–1.2 times as long as fore wing R1 vein) (Fig. 16); anterolateral area of the petiole bluntly costated (Fig. 39)................................ Aphidius colemani Viereck

18 Anterolateral area of petiole with 4–6 almost straight costulae (Fig. 40)............. Aphidius smithi Sharma & Subba Rao

- Anterolateral area of petiole with 7–14 irregular curved costulae (Figs 41, 42)..................................... 19

19 Fore wing stigma 1.5–2.2 times as long as fore wing R1 vein (Fig.18); propodeum with narrow pentagonal areola (Fig. 43); body generally dark-brown................................................ Aphidius eadyi Starý, Gonzales & Hall

- Fore wing stigma 1.1–1.35 times as long as fore wing R1 vein (Fig. 19); propodeum with wide pentagonal areola (Fig. 44); body generally yellow................................................................ Aphidius banksae Kittel