This paper is part of a series of new checklists to the British and Irish Hymenoptera fauna, that started with Broad and Livermore (2014b), Broad and Livermore (2014a) and Liston et al. (2014)and is the first update to the Hymenoptera checklist since 1978 (Fitton et al. 1978). Proctotrupoids are koinobiont endoparasitoids of holometabolous insect larvae. Although Proctrotrupidae can be common and readily collected by sweep netting or Malaise traps, the superfamily is poorly known biologically. Proctotrupidae are parasitoids of Coleoptera and, to a lesser extent, Diptera larvae, with one extraordinary host record from a centipede, whereas Heloridae have been reared from Neuroptera larvae (biology summarised in Gauld and Bolton 1988). Extralimital families attack Coleoptera and Neuroptera, or (Austroniidae, Peradeniidae, Proctorenyxidae) are completely unknown biologically.

The superfamily 'Proctotrupoidea' has generally been a welcoming home to a variety of parasitoid groups and recognised as not being monophyletic (Rasnitsyn 1988, Ronquist et al. 1999, Dowton and Austin 2001); in the 1978 checklist (Fitton et al. 1978) the Platygastroidea and Diaprioidea were included in the Proctotrupoidea. The removal of the Diapriidae, Maamingidae and Monomachidae to their own superfamily (Diaprioidea) has recently gained acceptance (e.g. Klopfstein et al. 2013). The Proctotrupoidea as presently defined (e.g. Sharkey 2007) now comprises the Heloridae and Proctotrupidae in Britain and the extralimital families Austroniidae, Pelecinidae, Peradeniidae, Proctorenyxidae, Roproniidae and Vanhorniidae.

There has been very little work on the British proctotrupoid fauna and most of what we know about the British and Irish Proctotrupidae derives from the global monograph of Townes and Townes (1981). Both families can be recognised instantly by their distinctive wing venation and they each have a characteristic habitus (Figs 1, 2, 3). A revision of the British fauna would undoubtedly reveal more species.

Much of the distribution data are taken from Townes and Townes (1981). Distribution data pertaining to Ireland are mostly from O'Connor et al. (2004). Other sources are referred to. There is an excellent online resource, The Proctotrupidae of the World. The taxonomy follows Townes and Townes (1981) and Townes (1977) with subsequent changes referenced. We have tried to account for every name on the 1978 checklist Fitton et al. (1978) and all additions to the fauna since then have been referenced. A more complete methodology and rationale behind the checklist can be found in Broad (2014). The following conventions and abbreviations are used here:

[species] taxon deleted from the British and Irish list

NHM Natural History Museum, London

# known or suspected introductions with at least temporarily self-sustaining populations

? status (including uncertain synonymy) or identification in the British Isles uncertain

misident. has been misidentified as this name

nom. dub. nomen dubium, a name of unknown or doubtful application

nom. ob. nomen oblitum, ‘forgotten name’, does not have priority over a younger name

nom. nov. nomen novum, a replacement name

nom. nud. nomen nudum, an unavailable name, with no type specimen

preocc. name preoccupied (junior homonym)

stat. rev. status revocatus, revived status (e.g., raised from synonymy)

unavailable not meeting the requirements of the International Code of Zoological Nomenclature

var. variety, only available as a valid name under the provisions of article 45.6 of the ICZN

Alternative versions of the checklist, as a formatted Word document and Excel spreadsheet, are provided here in the supplementary materials: Suppl. materials 1, 2.

Photographs were taken using a Canon EOS 450D digital camera attached to a Leica MZ12 stereomicroscope and partially focused images were combined using Helicon Focus v.4.80 software.