title: An illustrated key to the cuckoo wasps (Hymenoptera, Chrysididae) of the Nordic and Baltic countries, with description of a new species.
abstract: The Chrysididae are a group of cleptoparasitic and parasitoid aculeate wasps with a large number of rare and endangered species. The taxonomy of this group has long been confusing due to the similarity of species and extensive intraspecific variation. We present for the first time a comprehensive dichotomous key for all 74 species found in the Nordic and Baltic countries. In addition to diagnostic characters, information on the distribution and biology of each species is also presented. A new species, Chrysis borealis Paukkunen, Ødegaard & Soon, sp. n. is described on the basis of specimens collected from Fennoscandia. Chrysis gracillima Förster, 1853 is recorded as new to the Nordic and Baltic countries.
authors.affiliation: Finnish Museum of Natural History, Zoology Unit, P.O. Box 17, FI-00014 University of Helsinki, Finland.
authors.forename: Juho
authors.initials: J
authors.lastname: Paukkunen
authors.affiliation: Kämnarsvägen 33F 1201, 226 46 Lund, Sweden.
authors.forename: Alexander
authors.initials: A
authors.lastname: Berg
authors.affiliation: Natural History Museum and Institute of Ecology and Earth Sciences, University of Tartu, Vanemuise 46, 51014 Tartu, Estonia.
authors.forename: Villu
authors.initials: V
authors.lastname: Soon
authors.affiliation: Norwegian Institute for Nature Research - NINA, P.O. Box 5685 Sluppen, NO-7485 Trondheim, Norway.
authors.forename: Frode
authors.initials: F
authors.lastname: Ødegaard
authors.affiliation: Via Belvedere 8/d, I-20881 Bernareggio (MB), Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Rosa
keywords: Chrysis borealis sp. n.; Denmark; Estonia; Finland; Latvia; Lithuania; Morphology; Norway; Sweden; distribution; host species; phenology