Abstract
Up until now, three species of Liparis were recognized in Brazil. During floristic surveys of the orchid family in Brazil, populations of a Liparis species occurring in marshy areas were found. Based on our investigations we conclude that it is the rare L. inundata, a taxon currently considered to be a synonym of L. nervosa. Morphological, phenological and ecological evidence is provided for the recognition of L. inundata as a species distinct from L. nervosa. In addition, the original illustration of Barbosa Rodrigues is designated as the lectotype of L. inundata.