| Summary: | English summary: Land-snails in rich fens in the province of Västmanlands län (C. Sweden), with comments on the species and recommendations of conservation measures for the investigated objects At the request of the local nature conservation unit of the province of Västmanlands län, 18 fen objects were investigated for land molluscs 2007-2008. The location of all investigated sites is presented in Figur 1. The rich fens in the province of Västmanland can, according to the land mollusc fauna, mainly be classified as intermediary rich fens or transition fens to the extreme rich type. Pronounced extreme rich calcareous fens (often with springs) are rare, and only four of the investigated objects can be classified as such. Several of the fens are mosaics, with different types of transitions. More closed parts, which have to be classified as marsh forests, are often closely connected to the open fens. The most characteristic species for the intermediate rich fens is Vertigo lilljeborgi, which occurred in almost all the investigated sites. It is often accompanied by other, less demanding hygrophiles, such as Euconulus praticola and Deroceras laeve. In four of the richer fens the fastidious, rare and red-listed Vertigo geyeri was found – it can be considered a very characteristic species for the richest type of calcareous fen habitats. These records confirm the occurrence of the species in the province of Västmanlands län. Only one older, geographically bad defined record was previously known – and the species was considered extinct. In one site V. geyeri co-existed with the likewise rare and red-listed Perforatella bidentata – a species, which is known from a few sites in the area, mostly of more closed character (marsh forests). A few of the sites have a more eutrophic character and harbours Vertigo antivertigo, which is rare in the central and northern parts of Västmanland. The rich fens in the province of Västmanlands län are exclusively of the ‘woodland type’, dominating in Central and Northern Sweden. In this ...
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