Species richness and composition of epiphytic bryophytes in flooded forests of Caxiuanã National Forest, Eastern Amazon, Brazil

ABSTRACT This study aimed to compare the richness and composition of the epiphytic bryoflora between várzea and igapó forests in Caxiuanã National Forest, Brazilian Amazon. Bryophytes were collected on 502 phorophytes of Virola surinamensis. Average richness per phorophyte and composition between forests and between dry and rainy periods was tested by two-way analysis and by cluster analysis, respectively. In total, 54 species of 13 families were identified. Richness was greater in igapó forest (44 species) compared to várzea forest (38 species). There was no significant difference in the number of species between the studied periods. Cluster analysis showed the bryoflora composition was different between várzea and igapó, but not between dry and rainy periods. Results did not corroborate the hypothesis that várzea forests harbor higher species richness than igapó forests.