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 Taxon classification Animalia Hymenoptera Chrysididae Cleptes nitidulus (Fabricius, 1793) Figs 13, 14, 16 Ichneumon nitidulus Fabricius, 1793: 184. Cleptes nitidula : Fabricius 1804 : 154. Diagnosis. Length 5-7 mm. Both sexes differ from Cleptes semiauratus by not having a foveate furrow posteriorly on the pronotum (Fig. 13). The female also differs from Cleptes semiauratus by its black head and mesoscutum, non-metallic yellow or orange pronotum, mostly metallic blue mesoscutellum, metanotum and propodeum, and non-metallic black apex of the metasoma. As opposed to the female, the head and mesosoma of the male are entirely metallic green and the apex of the metasoma has faint metallic reflections laterally (Fig. 16). Both sexes differ from Cleptes semicyaneus by having pale brown or yellow (not dark brown) legs, denser punctation on the tergites (Fig. 16) and deep postocellar foveae on the vertex (Fig. 14). Distribution. Denmark, Estonia, Finland, Latvia, Sweden. Rare. - West Palearctic: Europe and Turkey ( Linsenmaier 1959 ), records from China are erroneous ( Rosa et al. 2014 ). Biology. Habitat: sparsely vegetated sandy areas, such as dry meadows and dunes ( Morgan 1984 ). Occasionally found on flowers of Apiaceae ( Heinrich 1964 ). Flight period: June to August. Host: Caliroa cerasi (Linnaeus) and Euura ribesii (Scopoli) ( Tenthredinidae ) ( Dahlbom 1854 , Morgan 1984 ).