Thirty four genera and 215 species of Myxomycetes are present in northeastern Brazil, covering 83 % of families, all subclasses and orders recognized for these microorganisms. Ceará, with an area of 148,825,602 km2, is one of the least explored of the nine states in this region of the country, with records of 27 species, distributed across 13 genera, occurring in a humid forest environment of the southern mesoregion. The dominant vegetation type is the Caatinga (dry, tree-shrub deciduous vegetation), with patches of Cerrado (savanna-like vegetation), Carrasco (montane deciduous shrub vegetation) and fragments of Pluvio-nebular Tropical Subperennial Forest and Pluvial Tropical Subdeciduous Forest. In order to better document the diversity of myxomycetes in that state, specimens were collected from the field between 2002-2007 in Ceará’s northern and northwestern mesoregions. The specimens obtained were deposited at the UFP Herbarium. Eighteen species were recorded, occurring in the Caatinga vegetation and the records of Comatricha, Craterium and Metatrichia increase the number of genera which comprise Ceará’s myxobiota to 16. Arcyria denudata, Craterium leucocephalum, Badhamia panicea, B. melanospora, Didymium intermedium, Metatrichia vesparia, Physarum rigidum and P. tenerum are new records for Ceará, increasing the number of species known to occur in the state to 37.
