Abstract
BACKGROUND: Species of Helorus Latreille 1802 are rarely collected endoparasitoids of Chrysopidae larvae (Neuroptera). Previous work on the limits between the European species of this species-poor genus, based on morphology only, has left some uncertainties. Here, we approach these cases and revisit previous taxonomic decisions using freshly collected and museum material. NEW INFORMATION: We generated the first large-scale Heloridae DNA barcode dataset, combined these with morphological data in an integrative taxonomic approach, and added information from studying all relevant type material. We found five species, Helorusanomalipes (Panzer, 1798), H.coruscus Haliday, 1857 stat. rev., H.nigripes Förster, 1856, H.ruficornis Förster, 1856, and H.striolatus Cameron, 1906, for which we provide an updated identification key. DNA barcode data are added to publicly available DNA barcode reference databases, for all species, except H.nigripes.