A first inventory of the myxomycetes for the Island of Mayotte is presented. The 270 specimens represent 27 genera, 75 species and 7 infraspecific taxa. First records for Africa include Arcyria glauca, Cribraria cf. tecta, Hemitrichia aurea, as well as Cribraria tenella var. concinna and Stemonitis fusca var. nigrescens. Systematic composition, general distribution, abundance or rarity and substrate or microhabitat preferences of individual species are discussed. A comparison with inventories made in the larger area suggests an important degree of endemism.