During the research of fen mollusc assemblages in Switzerland carried out in August 2012, we recorded the first occurrence of Vertigo lilljeborgi (Westerlund, 1871) in the Alps and several new occurrences of V. genesii (Gredler, 1856), substantially extending its Alpine distribution island towards the western part of the mountain range. Both these Euro-Asian species are mainly distributed in northern Europe and have a strong ecological affinity to groundwater-fed fens. With respect to the rarity, refugial character and high conservation value of central European populations of these species, we review in detail their ecological preferences and present European distribution, and also comment on the possible conservation implications for their globally threatened habitats.