Hedychrum gerstaeckeri Chevrier, 1869

Paukkunen, Juho, Berg, Alexander, Soon, Villu, Odegaard, Frode & Rosa, Paolo, 2015, An illustrated key to the cuckoo wasps (Hymenoptera, Chrysididae) of the Nordic and Baltic countries, with description of a new species, ZooKeys 548, pp. 1-116 : 30-31

Taxon classification Animalia Hymenoptera Chrysididae

Hedychrum gerstaeckeri Chevrier, 1869 Figs 56, 61

Hedychrum Gerstaeckeri Chevrier, 1869: 47.

Diagnosis.

Length 4-8 mm. The female differs from the females of other Hedychrum species by having a completely blue, violet-blue or green-blue mesosoma. As in Hedychrum rutilans , the female does not have an apicomedial tubercle on S3. Both sexes also have medially pale brown or yellowish mandibles. The male is similar to the female in colouration and can be confused with the males of Hedychrum niemelai and Hedychrum nobile . However, the punctation of T3 is coarser in Hedychrum gerstaeckeri (Fig. 61) and the mesotibial groove is longer and deeper (Fig. 56).

Distribution.

Denmark, Estonia, Finland, Latvia, Lithuania. Relatively common. - Trans-Palearctic: from western Europe to Japan, China and Taiwan ( Rosa et al. 2014).

Biology.

Habitat: sparsely vegetated sandy areas, dry meadows. Adults often visit flowers of Apiaceae , Asteraceae and Euphorbiaceae ( Trautmann 1927, Kusdas 1956, Kunz 1994, Linsenmaier 1997, Westrich 1979, Rosa 2004, our own obs.). Flight period: mid-June to late August. Host: Cerceris rybyensis (Linnaeus) and Cerceris ruficornis (Fabricius) ( Crabronidae ) ( Berland and Bernard 1938, Grandi 1961, Petit 1975, Westrich 1979, Brechtel 1985, Gayubo et al. 1987, Saure 1998).