The adults grow up to 7–10 millimetres (0.28–0.39 in) long, while the wingspan reaches 5–15 millimetres (0.20–0.59 in). They can mostly be encountered from May through August feeding on nectar and pollen of a variety of flowers (for instance of Lavandula stoechas, Cytisus scoparius, Thapsia villosa, etc.).
Their body is dark-brown and hairy, especially on the side of the abdomen. The wings have a light area located near the apex and a dark area close to costal margin, separated by a zig-zag division. The apex of cell R1 is hyaline. The dark area of the wings almost reaches the end of the abdomen.
The larvae are hyperparasites (parasites of parasites), mainly developing in larvae of flies (Diptera, Tachinidae), as well as in wasp larvae (Hymenoptera, Ichneumonidae) parasitizing caterpillars moths (Noctuidae).