A finding of the lymnaeid species Ladislavella occulta (Jackiewicz, 1959) [Mollusca: Gastropoda: Lymnaeidae] in Hungary is reported, which is the first record of this aquatic snail in the country. The shells of L. occulta were found in 1989 in the marsh area of the Bátorliget Nature Reserve. The current distribution of this species in Eastern and Central Europe is reviewed. It is hypothesized that L. occulta represents a relic species, whose origin may be traced back to the Pleistocene.