An illustrated key to the cuckoo wasps (Hymenoptera, Chrysididae) of the Nordic and Baltic countries, with description of a new species Author Paukkunen, Juho Author Berg, Alexander Author Soon, Villu Author Odegaard, Frode Author Rosa, Paolo text ZooKeys 2015 548 1 116 http://dx.doi.org/10.3897/zookeys.548.6164 journal article http://dx.doi.org/10.3897/zookeys.548.6164 1313-2970-548-1 D5D7B51E5AC6460D9B3C7584E46F9B3F D5D7B51E5AC6460D9B3C7584E46F9B3F Taxon classification Animalia Hymenoptera Chrysididae Chrysis graelsii Guerin-Meneville , 1842 Chrysis Graelsii Guerin-Meneville , 1842: 148. Chrysis Foerster , 1853: 309. Diagnosis. Length 7-9 mm. The colouration is unique among North European chrysidids. The head and mesosoma are blue or greenish, and the mesoscutum is medially often dark blue or nearly black. The metasoma is dorsally red, but the apical rim of T3 is contrastingly blue. Distribution. Estonia, Finland, Latvia, Lithuania. Relatively rare. - West Palearctic: Europe and Asia Minor ( Linsenmaier 1959 , 1968 ). Biology . Habitat: forest margins, clearings and gardens with sun-exposed dead wood. Adults are occasionally found on flowers of Apiaceae and Euphorbiaceae ( Poppius 1901 , Heinrich 1964 , Kunz 1994 , Linsenmaier 1997 ). Flight period: late May to mid-August. Host: Euodynerus notatus (Jurine) ( Vespidae ) ( Herrmann 1996 , Paern et al. 2014 , our own obs.), probably also Euodynerus quadrifasciatus (Fabricius) ( Saure 1998 ) and in Crimea Euodynerus disconotatus (Lichtenstein) ( Martynova and Fateryga 2015 ).