Molecular differentiation within European Cratoneuron filicinum, and differences from Asiatic and American populations

Variation in ITS and the two chloroplast markers rpl16 and tRNA-Gly was studied to explore phylogeographic patterns in, especially, western Eurasiatic Cratoneuron filicinum (Hedw.) Spruce. ITS and chloroplast data yield incongruent results and are therefore analysed separately; recombination is indicated for ITS. For both data sets one group of haplotypes is widespread in western Eurasia. Another is found in the Mediterranean region and occurs in southern Scandinavia (ITS) or large portions of northern Europe, but is missing in central Europe. It is suggested that the northern populations of the latter haplotypes have dispersed from eastern or south-eastern glacial refugia. At the continental scale, south-east Asiatic populations differ from those in western Eurasia, with an apparent meeting zone west of the Himalayas. American haplotypes are most similar to some European ones according to ITS, but to south-east Asiatic ones according to chloroplast data.