Any plant of the genus Bougainvillea, comprising about 14 species of shrubs, vines, or small trees (family Nyctaginaceae) native to South America and hardy in warm climates. Many species are spiny. Only the woody vines are widely popular; showy cultivated varieties of several species are often grown indoors. The inconspicuous flowers are surrounded by brightly coloured papery bracts, for which one species, B. glabra, is called paperflower. The bracts of various species range from purple to lemon-yellow.