• Bryum;
  • molecular phylogeny;
  • nuclear ribosomal DNA internal transcribed spacer sequences;
  • Ptychostomum;
  • rps4 sequences

Abstract  The phylogeny of Ptychostomum was first undertaken based on analysis of the internal transcribed spacer (ITS) region of the nuclear ribosomal (nr) DNA and by combining data from nrDNA ITS and chloroplast DNA rps4 sequences. Maximum parsimony, maximum likelihood, and Bayesian analyses all support the conclusion that the reinstated genus Ptychostomum is not monophyletic. Ptychostomum funkii (Schwägr.) J. R. Spence (≡Bryum funkii Schwägr.) is placed within a clade containing the type species of Bryum, B. argenteum Hedw. The remaining members of Ptychostomum investigated in the present study constitute another well-supported clade. The results are congruent with previous molecular analyses. On the basis of phylogenetic evidence, we agree with transferring B. amblyodon Müll. Hal. (≡B. inclinatum (Brid.) Turton ≡Bryum archangelicum Bruch & Schimp.), Bryum lonchocaulon Müll. Hal., Bryum pallescens Schleich. ex Schwägr., and Bryum pallens Sw. to Ptychostomum.