Hydroglyphus hamulatus (Gyllenhal, 1813) (Coleoptera, Dytiscidae), a predaceous diving beetle species new to the Czech Republic

We report the occurrence of the predaceous diving beetle Hydroglyphus hamulatus (Gyllenhal, 1813) in the Czech Republic. Specimens were collected between 2021 and 2024 at post-mining lakes Most and Milada, with an additional record from 1986. These data raise the number of Czech diving beetles to 127 confirmed and eight questionably present species. The new records likely reflect a recent European migration wave and highlight the conservation value of post-mining lakes, a habitat resembling northern European oligotrophic lakes that are rare in Central Europe.