Abstract
BACKGROUND: The checklist of British and Irish Ichneumonidae is revised, based in large part on the collections of the Natural History Museum, London and the National Museums of Scotland, Edinburgh. Distribution records are provided at the country level. NEW INFORMATION: Of the 2,447 species regarded as valid and certainly identified, 214 are here recorded for the first time from the British Isles. Neorhacodinae is considered to be a separate subfamily rather than a synonym of Tersilochinae. Echthrini is treated as a junior synonym of the tribe Cryptini, not Hemigastrini. Echthrus Gravenhorst and Helcostizus Förster are classified in Cryptini rather than, respectively, Hemigastrini and Phygadeuontini.