Abstract
The floristic composition of epiphytic bryophytes on trunks of the tree ferns species Cyathea arborea and Dicksonia sellowiana was studied in SE-Brazil. A total of 142 bryophyte species were found, of which 20 were found in more than 10% of the vegetation analyses, 77 species occurred only one to three times.
Five new bryophyte associations are described in two new classes: the Syrrhopodetum proliferi, Porotricho-Syrrhopodetum incompleti and Orthostichello-Syrrhopodetum parasitici within the Hymenodontetalia aeruginosae, which is almost confined to Caythea arborea. They prefer humid habitats in coastal rain forests and cloud forests. The Campylopodetum extincti and Campylopodetum occculti are united within the class Syrrhopodetalia gaudichaudii. They grow on Dicksonia sellowiana and occur within Araucaria forests.
The predominant life form in both classes are wefts and mats. The characteristic life forms of the Hymenodontetalia are short turfs, dendroids, fans and tails, which are an expression of the humid habitat conditions, but short and tall turfs in the Syrrhopodetalia.