From November/2003 to November/2004, water and soil samples were collected every three months in the Paranapiacaba Biological Reserve, an important fragment of Brazilian Atlantic rain forest, to study Oomycota diversity. To isolate these organisms, the samples were treated by the baiting technique, which resulted in the identification of 35 species: one belongs to Leptomitales, four to Peronosporales, two to Rhipidiales and 28 to Saprolegniales; in this paper we describe and illustrate, with comments, the species already mentioned for Brazil. Three are cited for the first time for São Paulo state, Leptolegnia eccentrica Coker & Matthews, Pythiopsis humphreyana Coker and Pythiopsis irregularis Seymour, and 20 for this area.
diversity; zoosporic fungi; Brazil; Atlantic rain forest; Oomycetes
