Hydrothassa marginella, (LINNAEUS, 1758)

Alekseev, Vitaly I. & Bukejs, Andris, 2010, Contributions to the knowledge of beetles (Insecta: Coleoptera) in the Kaliningrad region. 1., Baltic Journal of Coleopterology 10 (2), pp. 157-176 : 169

44. HYDROTHASSA MARGINELLA (LINNAEUS, 1758) Examined material: Recorded from only three localities: Zelenogradsk environs, 54°57´11.6´´N 20°29´11.7´´E, 09.V.1998 (1 ex., the Baltic Sea coast, leg. V. Alekseev), 5 km NE Zelenogradsk , 54°58´12.9´´N 20°31´37.3´´E, 11.V.2009 (3 exx., wet shore of the Curonian Gulf, on Caltha palustris , leg. V. Alekseev); Zelenogradsk district, 1 km W Svetlogorsk, 54°56´6.5´´N 20°6´29.4´´E, 14.V.1997 (1 ex., the Baltic Sea coast, leg. V. Alekseev) .

Comments: On the territory of the former East Prussia, this species has been reported from Palmnicken [Yantarny], Königsberg [Kaliningrad], Insterburg [Chernyakhovsk], Trempen [Novostroevo in Ozersk district] ( Bercio & Folwaczny 1979). The species is widely distributed across the whole Baltic and Fennoscandian region and has been reported from all territories ( Silfverberg 2004) and also from Belarus (Alexandrovich et al. 1996). The species feeds on Ranunculaceae ( Caltha , Ranunculus ).