Veronika Schenková

Refugial Populations of Vertigo lilljeborgi and V. genesii (Vertiginidae): New Isolated Occurrences in Central Europe, Ecology and Distribution

Abstract: 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.

Fossil Records of Marstoniopsis insubrica (Küster, 1853) Suggest Its Wide Distribution in Central Europe During the Early Holocene

The rare and endangered freshwater snail Marstoniopsis insubrica (Kuster, 1853) (Gastropoda: Amnicolidae) today has a highly disjunct distribution in Europe. We abstracted all known published Holocene fossil records of Marstoniopsis insubrica, previously reported as M. scholtzi. The early Holocene records from Hungary together with the new record from southern Slovakia fill a distribution gab between northern and southern present populations. Because of the presence of continental ice sheet that covered much of northwestern Europe during the last cold stage, it is likely that the modern distribution of M. insubrica in most of northern Europe is of postglacial origin. These fossil records can therefore suggest a possible dispersal pathway of postglacial spreading from southern refugia to the north, in a southeastwards direction along the Alps, thought the location of its glacial refugia are unknown.