Thirteen taxa of Mucorales (Zygomycotina), distributed in 266 occurrences were isolated from leaves of Alchornea triplinervia (Spreng.) Müll. Arg. disposed in the terrestrial and aquatic environment, and of soil and stream water samples, monthly taken from July of 1988 to May of 1990, in the "Reserva Biológica do Alto da Serra de Paranapiacaba", in the municipality of Santo André, São Paulo State, Brazil. Mucor hiemalis Wehmer (78 records), Mucor circinelloides van Tieghem f. janssenii (Ledner) Schipper (42 records) and Rhizopus arrhizus Fischer (30 records) were the most frequent species. Fifty percent of the Mucorales found are formed by species that are mentioned for the first time in the Atlantic Rainforest: Mucor hiemalis Wehmer f. silvaticus (Hagem) Schipper, Rhizopus arrhizus Fischer, Rhizopus oligosporus Fischer, Rhizopus oryzae (Went. & Prinsen) Geerlings, Zygorhynchus japonicus Vuill. and Zygorhynchus macrocarpus Ling-Young.
Atlantic Rainforest; Zygomycotina; Mucorales; diversity; Alchornea triplinervia