XVI International Botanical Congess

There are 23 taxa of Asclepiadaceae R.Br. in sandy coastal plain vegetation (restinga), Rio de Janeiro state. These plants are climbers, usually growing in open, sunny areas, and less commonly found in the shade of thickets, at forest's edge or in swampy areas. Eight taxa are restricted to restinga vegetation, five are endemic to Rio de Janeiro state: Ditassa maricaensis, Gonolobus dorothyanus, Orthosia arenosa, Oxypetalum banksii subsp. corymbiferum and Marsdenia hilariana var. macieliana. Due to loss of restinga habitat, Ditassa arianeae, Ditassa maricaensis and Gonolobus dorothyanus have been classified as vulnerable or threatened with extinction.