Abstract
Dung represents an important survival resource for a wide range of microorganisms, including free-living Amoebozoa such as Myxomycetes. This group encompasses just over 1,000 morphologically recognizable species, occupying different ecological niches; however, only about 10% of them act as cyclers of the organic matter and energy egested by herbivorous animals, forming the ecologically known group called fimicolous. In this study, new occurrences of fimicolous myxomycetes are presented for Brazil, originating from the Pampa biome, including Perichaena pachyderma D.W. Mitch., G. Moreno and Lizárraga and Perichaena taimyriensis Novozh. and Schnittler, which are recorded for the first time in the Americas.