A key to the European genera of diplazontine ichneumon‐flies, with notes on the British fauna

Abstract
The thirteen European genera of Diplazontinae (Hymenoptera) are keyed. Notes are given, with reference to the British fauna, on their identification, nomenclature and biology. Particular attention is paid to their associations with aphidophagous Syrphidae (Diptera). One new synonymy is established.