Factors affecting population size and vitality of Hamatocaulis vernicosus (Mitt.) Hedenäs (Calliergonaceae, Musci)
A molecular study of the wetland pleurocarpous moss Hamatocaulis vernicosus (Mitt.) Hedenäs, based on the ITS region, the trnL-trnF region, and rpl16 revealed two cryptic species. One of these is widespread in Europe, and was also sampled from several localities in Minnesota (United States). The other cryptic species occurs only south of the boreal zone in Europe, and was in addition sampled from single localities in Peru and northernmost Asiatic Russian Federation. Although it seems likely that the southern species colonized parts of Europe from southern refugia after the last glaciation, its wide distribution outside Europe indicates that the speciation event is unrelated to the European glacial history. No correlations could be found between variation in habitat preferences (pH and electric conductivity) and molecular variation.