Abstract
The pitcairnioid genus Fosterella currently comprises 31 species distributed from Mexico in North America, along the eastern slopes of the Andes in central South America, Southern Peru to northern Argentina, encompassing western, northern and southeastern Brazil and northern Paraguay. Their species have rather small ranges, representing local endemics traditionally difficult to circumscribe mainly because the presence of subtle morphological characters associated to tiny floral parts. The present taxonomical study of the Fosterella species occurring in Brazil is founded on morphological characters, habitat preference, and geographic distribution. The number of Brazilian species is increasing to eight, three of them described as new here, including an unexpected outlier in geographical range and two new records for the country. Full descriptions and an identification key are provided, and morphological relationships are discussed as well.