This paper is a characterization of the desmid florula of the São João River, Iguaçu National Park, Foz do Iguaçu, Paraná, Brazil. Samples were collected in the period from June 2008 to May 2009 in three sampling stations of the São João river. The samples were obtained with a 25 µm nylon plankton net was immediately fixed on Transeau solution. 44 taxa were identified distributed among the genera Actinotaenium (1), Bambusina (1), Closterium (7), Cosmarium (11), Desmidium (1), Euastrum (2), Gonatozygon (3), Micrasterias (5), Netrium (1), Octacanthium (1), Pleurotaenium (1), Spondylosium (2), Staurastrum (4), Staurodesmus (2), Teilingia (1), and Xanthidium (1). Cosmarium Corda ex Ralfs was the most representative genus in the study, with 25% of the local documented taxa.
desmids; river; taxonomy; Zygnemaphyceae
