An integrative taxonomic study of European Eupelmus (Macroneura) (Hymenoptera: Chalcidoidea: Eupelmidae), with a molecular and cytogenetic analysis of Eupelmus (Macroneura) vesicularis: several species hiding under one name for 240 years

The European species of Eupelmus (Macroneura Walker), including the cosmopolitan and extremely polyphagous species Eupelmus vesicularis (Retzius), are revised using an integrative approach. DNA sequences of the D2 expansion region of the 28S ribosomal subunit (28S-D2) and the mitochondrial cytochrome oxidase c subunit I (COI), karyological, and new morphological evidence are used to demonstrate that several cryptic species have been included under the name E. vesicularis in Europe and the species Eupelmus impennis Nikol’skaya was misinterpreted in the past. Eupelmus messene Walker, described from a specimen collected in New Zealand by Charles Darwin, is removed from synonymy under E. vesicularis and treated as a cosmopolitan valid species. The biological attributes that promoted the successful colonization of new territories by this species are discussed. Neotypes are designated for Eupelmus messene and Ichneumon vesicularis, and lectotypes for Eupelmus degeeri Dalman, Eupelmella maculata Ferrière, and Eupelminus coleopterophagus Girault. Four new species are described: Eupelmus (Macroneura) balcanicus sp. nov. and E. (Macroneura) rameli sp. nov. from the Balkan Peninsula, E. (Macroneura) barai sp. nov. from throughout Europe except from the north and Eupelmus (Macroneura) vladimiri sp. nov. from the Balkan Peninsula and Middle East. The first three species and E. messene were previously included under E. vesicularis introducing a lot of uncertainty into the extensive literature under this name. Morphological limits of the species are discussed. Males of five species are recognized and diagnosed for the first time. A key to females of 12 species and known males of European Eupelmus (Macroneura) is provided. The key illustrations and differential diagnoses provided will help in the confident identification of this species in the future and benefit ecologists and researchers involved in the biological control of insect pests.Author’s visits to BMNH, HNHM, MNCN, and MNHN were supported by the SYNTHESYS Project (http://www.synthesys.info/), financed by European Community Research Infrastructure Action under the FP7 ‘Capacities’ Program (GB-TAF-490, HU-TAF-2949, ES-TAF-1816, and FR-TAF-1155), and his research is currently sustained by the internal grant GI-2015-02 awarded by the Al. I. Cuza University of Iaşi.Peer reviewe