Bougainvillea, Gen. Pl.: 91. 1789, nom. cons., sec. Bittrich & Kühn (1993)
Standley and Steyermark (1946) state that Bougainvillea contains c. 14 species native to South America, three of which were cultivated in tropical and subtropical regions of the world. According to Fay (1980), the genus includes 10 species, but the author argued that artificial selection processes, hybridization and the spread of clonal variants have produced a complex pattern of variation only loosely related with any natural group. Gillis (1976) treated the Bougainvilleas of cultivation considering three species and one hybrid. The biology, the artificial selection as well as the lack of a monographic treatment make it difficult to determine the current number of species.