ON THE POSSIBLE ORIGIN AND TAXONOMIC STATUS OF HYPNUM HESELERI ANDO & HIGUCHI

Abstract

  The origin and taxonomic status of Hypnum heseleri Ando & Higuchi is discussed. Two hypotheses are proposed: a) the species reached western Europe recently by aerial long-distance dispersal, e.g. from Latin America north of the equator, b) the species is a recent mutant of Hypnum cupressiforme. There is a conflict in evidence between morphology and the electrophoretic data. On the basis of the morphology it is justified to describe the new taxon as a new species, but the electrophoretic data suggest that H. heseleri has no separate gene-pool with H. cupressiforme. In this special case of conflicting evidence we would prefer not to describe the taxon because the electrophoretic data are supported by cross-fertilization data and by the results of culture experiments. This is also the reason why we suppose the second hypothesis as being the most likely one.