Although the Thelypteridaceae has been treated for North America, Mesoamerica, Guayanas, Ecuador, Peru, Argentina, and the South and Southeast of Brazil, the central region of South America still requires updating. With this aim, the Thelypteridaceae of Paraguay and central Brazil were studied and comprise two genera, five subgenera, and 55 specific and infraspecific taxa. A general key for the groups and their entities, distribution, ecology, and illustrations are also provided. A new combination, new synonymys, and expanded distributions are included, and nomenclatural problems and taxonomic questions are discussed. Although the studied area is larger than other well studied regions, the total number of species is smaller in agreement with the low richness of environments.
Central South America; diversity; Macrothelypteris; Thelypteris
