Patterns of relationships in Trichostomoideae (Pottiaceae, Musci)

Ribosomal DNA sequences were employed to infer relationships among European Pottiaceae. Intragenic spacer I was sequenced for six Trichostomoideae (Eu cladium verticillatum, Pleurochaete squarrosa, Tortella flavovirens, T. nit ida, T. tortuosa, Trichostomum brachydontium) and seven taxa from the other European subfamilies included in Pottiaceae (Bryoerythrophyllum recurviros trum, Didymodon vinealis, Microbryum starkeanum, Tortula muralis, Syntrichi a ruralis, Weissia controversa and Timmiella cf. barbuloides). Cladistic an alysis of sequence data shows close relationships between Pleuvochaete, Tor tella and Weissia. Tortella appears to be paraphyletic, as it includes Pleu rochaete, Weissia and Trichostomum. Weissia, therefore, seems to be better placed in Trichostomoideae than, as traditionally done, in Pottioideae. Nei ther Merceyoideae nor Pottioideae appear to be monophyletic sensu stricto, at least within the limits of the taxa in analysis. Within the latter subfa mily, Syntrichia is clearly separated from Tortula. These results would sug gest that taxonomy in Pottiaceae does not depict the pattern of descent, an d therefore is in need of revision.