XVI International Botanical Congess

Complete 18S rDNA sequence data of 65 bryophyte species, representatives of all the classes, were used to infer a molecular phylogeny of bryophytes. The results reveal that the liverworts have to be divided into two separate classes, the Marchantiopsida, including Marchantiales and Sphaerocarpales, completely separated from the Jungermanniopsida, including the Metzgeriales and Jungermanniales. The Jungermanniopsida form together with the Bryopsida a sister clade to all Marchantiopsida, a result which was obtained with bootstrap values between 97 and 100% in all phylogenetic constructions, irrespective of the method used. The molecular analysis in general confirms the existing classification based on morphological data. The results of the large ribosomal unit (25S) of 12 bryophytes reflect the same separation between Jungermanniopsida and Marchantiopsida as the one indicated by the small subunit (18S) data.