Key to female aphidiine parasitoids of blueberry aphid, Ericaphis fimbriata in the Pacific Northwest

1 Forewing with 4 enclosed cells along anterior margin (R, 1M, 1R1, 2R1) (Fig. 2 e)....... Ephedrus incompletus Provancher

- Forewing with less than 4 enclosed cells along anterior margin (Fig. 1 a, Fig. 2 a–d, f–h)............................. 2

2 Forewing Rs + M vein present ( Praon) (Fig. 2 g)........................................................... 3

- Forewing Rs + M vein absent (Fig. 1 a, 2a–d, f, h)........................................................... 4

3 Antenna with 14–16 segments........................................................... Praon unicum Smith

- Antenna with 17–18 segments........................................................ Praon occidentale Baker

4 Forewing M & m-cu vein complete (Fig. 1 a, Fig. 2 a–d)....................................................... 5

- Forewing M & m-cu vein incomplete or absent (Fig. 2 f, h).................................................... 9

5 Forewing r-rs vein near perpendicular to stigma (Fig. 2 a)......................................... Monoctonus spp.

- Forewing r-rs vein not perpendicular to stigma (Fig. 1 a, Fig. 2 b–d).............................................. 6

6 Maxillary palp 3-segmented; labial palp 2-segmented; antenna with 14–15 segments......... Aphidius matricariae Haliday

- Maxillary palp 4-segmented; labial palp 3-segmented; antenna with at least 15 segments............................ 7

7 Antenna with 15–16 segments......................................... Aphidius ericaphidis Pike & Starý, sp. nov.

- Antenna with 17–18 segments........................................................................... 8

8 Petiole (= metasomal tergum 1) rugose (Fig. 1 f)............................................ Aphidius ervi Haliday

- Petiole costate (Fig. 1 e)............................................................... Aphidius vaccinii Liu

9 Forewing r-m present (Fig. 2 f); metasomal sternite VII without distinctive paired prongs.. Lysiphlebus testaceipes (Cresson)

- Forewing r-m absent (Fig. 2 h); metasomal sternite VII with distinctive paired prongs.............. Trioxys gahani Smith