New Cenozoic aquatic beetles of the families Dytiscidae (Cybister cf. rotundatus Říha 1974 and Cybister sp.) and Hydrophilidae (Hydrophilus cf. pistaceus Laporte de Castelnau 1840 and Hydrobiomorpha enspelense Wedmann 2000) are described and compared with recent relatives based on external morphological structures. All specimens are preserved in Oligocene and Miocene fluviolacustrine deposits of the Krušné hory piedmont basins (Bílina Mine, Czech Republic) and the Hrádek Basin (Seifhennersdorf, Germany).
Generic classifi cation of Cybister nicoleti Heer 1862 (Miocene) is discussed. Based on the confi rmation of generic identifi cation of Hydrobiomorpha enspelense, the occurrence of the circumtropical recent genus Hydrobiomorpha Blackburn 1888 in European Miocene deposits is confirmed.