First record of the greater white-toothed shrew, Crocidura russula, in the Czech Republic.

While sampling house mice in 2022 in the westernmost region of the Czech Republic, we also captured other small mammal species in and around farms. The sympatric shrew species were pre-identified based on morphological characteristics and genotyped using the mitochondrial cytochrome b marker. Among them, 14 specimens from five different localities were identified as the greater white-toothed shrew (Crocidura russula). With previous records from southern Saxony in Germany, our findings are the easternmost records of C. russula distribution in Europe and the first report of this species in the Czech Republic. The four other shrew species captured during fieldwork (C. suaveolens, C. leucodon, Sorex minutus, and S. araneus) are widely distributed in this country. The checklist of Eulipotyphla from the Czech Republic, which currently lists ten species (C. leucodon, C. suaveolens, S. alpinus, S. araneus, S. minutus, Neomys milleri, N. fodiens, Talpa europaea, Erinaceus europaeus, E. roumanicus), should now be updated with this new entry. The arrival of C. russula in the Czech Republic should be closely monitored as this species has been regularly reported for its competitive behaviour leading to the local extinction of resident shrew species. [ABSTRACT FROM AUTHOR]