Key to European species of Clistopyga

1. Metapleuron punctate (FIgs 1, 1, 3). Male face yellow or at least with yellow spots (FIgs 2, 1, 2). ............ 2

— Metapleuron smooth or granulate (FIgs 1, 5, 7). Male face black (FIgs 2, 3, 4). ........................................... 3

2. Ovipositor more-or-less uniformly up-curved, the length is about 1.5 × length of hind tibia (FIg. 1, 4). Metapleuron uniformly punctate (FIg. 1, 3). Hind coxa and femur without yellow marks. Male face with yellow spots (FIg. 2, 1). ......................................................................................................................... C. rufator

— Ovipositor strongly apically up-curved, the length is about 1.8–1.9 × length of hind tibia (FIg. 1, 2). Metapleuron more densely punctate distally, often impunctate proximally (FIg. 1, 1). Hind coxa and femur at least partly yellow. Male face entirely yellow (FIg. 2, 2). ................................................ C. incitator

3. Metapleuron smooth, impunctate (FIg. 1, 5). Hind femur entirely red. Ovipositor weakly apically upcurved, the length is about 1.4–1.5 × length of hind tibia (FIg. 1, 6). ...................................... C. canadensis

— Metapleuron granulate (FIg. 1, 7). Hind femur red, apically fuscous. Ovipositor strongly uniformly upcurved, the length is about 1.2 × length of hind tibia (FIg. 1, 8). ................................................... C. sziladyi