AbstractThe work was undertaken to investigate the mycoflora of the river Pisa and its tributary, the river Skroda. Samples of water were collected once a month over four years (1984 … 1987) for hydrochemical analysis and studies of the fungus content. Forty‐three species of fungi were found in these rivers. The following fungi unknown in Poland were found in the Pisa river:Achlya megaspermaandRhipidium partenospo