In Brazil, Eriocaulaceae comprises about 600 species distributed in eight genera. The main diversity center is the Espinhaço Range, where most of the taxonomic efforts are concentrated. However, sand dunes also have significant species diversity. This paper presents the floristic treatment of the Eriocaulaceae from the sand dunes of Rio de Janeiro state. A total of 12 species distributed in six genera were recorded; one of Actinocephalus, two of Comanthera, three of Leiothrix, three of Paepalanthus, two of Syngonanthus and one of Tonina. Most species were found in sandy, dry sites with few plants, and only one species was found in moist sites with lots of greenery. Illustrations, descriptions, an identification key, as well as comments on geographic distribution and morphological variation are provided.
flora; Leiothrix; Paepalanthus; Syngonanthus; taxonomy
