The pathogenic chytrid fungus Batrachochytrium dendrobatidis threatens the amphibian diversity at global scale. Three different strains of B. dendrobatidis have been already found in Brazil, the country with the greatest diversity of anurans worldwide, and it is widely spread in the Atlantic rainforest. Here, we report the occurrence of B. dendrobatidis for the state of Alagoas, the second record from northeastern Brazil. We describe for the first time B. dendrobatidis infection in Aplastodiscus sibilatus, a Brazilian tree frog species. The impact of B. dendrobatidis on populations of Brazilian anurans is unknown and information on spatial and taxonomic distribution of this fungus in Brazil is urgently needed for the development and implementation of amphibian conservation action plans.