ABSTRACT: The taxonomic study of filamentous fungi isolated from the rhizosphere of melon (Cucumis melo cv. Gold Mine) plantations treated with different combinations of organic composts reveals five species — Chaetomium convolutum, C. ochraceum, C. trigonosporum, Thielavia fragilis and T. microspora — documented for the first time in Brazil. Keys to all known Brazilian species of Chaetomium and Thielavia are also provided.

KEYWORDS: ascomycetes, taxonomy