Diversity of lotic macroalgae has been scarcely studied in Brazil. Floristic studies have not been recently published with a lack of information about ecology and taxonomy of these groups. Therefore, the present work aimed to survey macroalgae species from streams of the Serra do Japi, an area of Semideciduous Seasonal Forest (23º12’-23º21’ S and 46º30’-46º05’ W). We sampled 16 streams and we identified 16 taxa (11 infrageneric, 4 generic and one life stage, ‘Chantransia’), distributed in four divisions. Cyanobacteria was the best well represented group, with about 38% of the species, followed by Rhodophyta with approximately 31% of the taxa sampled. The sporophyte stage ‘Chantransia’ and Phormidium aerugineocaeruleum were the most widespread, occurring in 50% and 29% of the streams investigated, respectively. The knowledge about the composition and occurrence of macroalgae species can provide valuable information for decision-making on conservation of water resources, particularly in protected areas as Serra do Japi.
conservation; lotic algae; atlantic rainforest; taxonomy