XVI International Botanical Congess

In contrast to Homobasidiomycetes, heterobasidiomycetous fungi have a surprisingly high percentage of diverse and systematically important features and character transformations which are sometimes correlated with each other, indicating a general, i.e. organismic evolutionary strategy. These are, inter alia: repeated derivation of holobasidia from phragmobasidia, loss of active spore discharge, loss of flexibility in spore germination and loss of an ontogenetic yeast stage. In contrast, there is a gradual increase in complexity of septal pore types. Such diversity of principal characteristics is unknown in Homobasidiomycetes. -An overview of monophyletic groups in heterobasidiomycetous fungi is given. Key-taxa for the understanding of phylogenetic connections, and the new system of smuts will be explained. Molecular taxonomy has confirmed terminal taxa and offered hypotheses for better understandings of phylogenetic connections.