Phylogenetic relationships among the traditional taxa of the Bryaceae have been highly contentious due to uncertainty associated with homology assessment of morphological characters within the family. In particular, the reliance on sporophytic characters for the delimitation of genera has been questioned. Previous analyses based on molecular data have provided insights into the evolution of the group and established a framework for classification. Following these analyses, the Bryaceae has recently been recircumscribed to include only those members of the traditional sub-family Bryoideae (except Leptobryum), namely, the genera Acidodontium, Anomobryum, Brachymenium, Bryum, Plagiobryum, and Rhodobryum. Here we present analyses based on chloroplast DNA sequences (rps4 and trnL-trnF) to evaluate phylogenetic relationships within the recircumscribed family. The deepest division within the Bryaceae resolves a clade containing Rhodobryum, Brachymenium section Leptostomopsis, and Bryum section Capillaria subsection Rosulata as the sister group to the remaining sections of Bryum, plus Brachymenium sect. Dicranobryum, Acidodontium, Anomobryum, and Plagiobryum. Within the latter clade, section Capillaria, section Leucodontium subsection Calophylloideae, and section Caespiticia subsection Cernuiformia of Bryum are resolved with Plagiobryum. Within the sister group to this clade, section Bryum and Caespiticia subsection Caespiticia of Bryum form a clade with Brachymenium section Dicranobryum, Anomobryum is resolved as sister to Acidodontium, and Bryum sections Limbata and Apalodictyon subsection Alpiniformia form a clade. These analyses provide a preliminary basis for the interpretation of natural groups and morphological evolution in the Bryaceae.

Key words: Bryaceae, Bryum, phylogenetic relationships, rps4, trnL-F