关键词: 真藓科, ITS, 系统发育, 丝瓜藓属, Ptychostomum

Abstract: The Bryaceae phylogeny was reconstructed based on the internal transcribed spacer (ITS) region of the nuclear ribosomal DNA. Both Maximum parsimony and Bayesian inference analyses of ITS sequences revealed two well supported ingroup clades. One lineage contained Pohlia species whereas the other lineage contained species from five other genera—Rhodobryum, Brachymenium, Bryum, Plagiobryum and Anomobryum. Inconsistent with previous chloroplast DNA phylogenies, the ITS tree showed that the genus Pohlia was not more closely related to the outgroup family Mniaceae than to Bryaceae. In the other lineage, some Bryum species, such as B.algovicum, B.capillare, B.pallescens, B.pallens, B.pseudotriquetrum, B.uliginosum, B.amblyodon, B.caespiticium and B.lonchocaulon, clustered with high support with Plagiobryum zierii, which was also suggested by other molecular datasets. Based on the ITS tree, we supported the proposed shift for these Bryum species and Plagiobryum zierii to the genus Ptychostomum.

Key words: Bryaceae, ITS, phylogeny, Pohlia, Ptychostomum