The genus Qualea is found in tropical South America, particularly in the Hylaea and in the Extra Amazonian part of the Brazilian mainland (see fig. 3); it comprises 59 species as defined in this paper. Many species are forest trees occurring in the Amazonian basin, a number are found in the Brazilian Atlantic coastal forests, whereas other species are typical trees of the campos of the interior plateau. The genus was first described by AUBLET in 1775; its name is a latinization of the vernacular name “Qualé” used by the “Caribbean” inhabitants of French Guiana. AUBLET described O. rosea (type species) and Q. coerulea; the first exhaustive and morphologically correct description was given by A. DE ST. HILAIRE (1820) who placed the genus in his newly established family of the Vochysiaceae.