Olyreae (Poaceae: Bambusoideae) da Marambaia, Rio de Janeiro, Brasil

marambaia is located in southern rio de janeiro state, between sepetiba bay and the atlantic ocean (23o1's, 23o6's; 43o34'w, 44ow), within the atlantic forest domain. the tribe olyreae includes the herbaceous bamboos, found mainly in the new world tropics, usually comprising the herbaceous layer of forests. they are being threatened by habitat fragmentation and degradation. this study aims to determine which olyreae species occur in the area, contributing to our knowledge of their conservation, distribution and diversity. samples were collected from august 2008 to december 2010 by free walks along trails in the various plant formations. the occurrence of seven olyreae species distributed in atlantic slope-forest areas was confirmed. subtribe olyrinae is represented by cryptochloa capillata, olyra humilis, o. latifolia, parodiolyra micrantha, raddia brasiliensis and reitzia smithii, and subtribe parianinae by eremitis sp. olyra latifolia and p. micrantha are the most common species in the area. eremitis sp. is probably a new species.