As in most other mountain systems, in the European Alps there is a great difference between the floristic composition of plant communities growing on limestone and on siliceous bedrock. The geological situation of large parts of the Alps - a central siliceous core is flanked by peripheral limestone ranges - allows straightforward localization of peripheral Pleistocene refugia for plants growing on limestone. For silicicolous plants, this is not possible. In our study we want to localize glacial refugia for the latter based on the comparison of phylogeographic patterns of several vascular plant taxa with palaeoclimatological data and patterns of endemism. The investigated taxa exhibit contrasting distribution patterns and have different ecological demands, but are all confined to siliceous bedrock. Our sampling covers at least their entire distributional areas in the Alps. This comparative phylogeographical approach allows to search for common features and to avoid miss-interpretation of individual cases. We present phylogeographies of Androsace alpina, A. brevis, A. wulfeniana (Primulaceae), Comastoma tenellum (Gentianaceae), Phyteuma globulariifolium (Campanulaceae) and Saponaria pumila (Caryophyllaceae) inferred from AFLP-fingerprinting. In spite of differences in details there is a congruence in most phylogeographic patterns indicating the existence of several peripheral Pleistocene refugia. There are no hints for glacial survival in the formerly most extensively glaciated areas in the highest and most central parts of the Alps, i.e. "nunatak" regions defined by classical biogeographers early in this century. In contrast, our data do indicate survival in peripheral refugia and on peripheral nunataks close to the margin of the Pleistocene ice sheet.

Key words: AFLP, comparative phylogeography, endemism, European Alps, glacial refugia, nunatak