Browallia Linnaeus (Solanaceae, Cestroideae) is native to the New World tropics and subtropics. Taxonomists first grouped Browallia and morphologically similar genera within the Salpiglossideae, which were considered advanced in Solanaceae because of their derived characters. Recent evidence indicates that Salpiglossideae is paraphyletic within the subfamily Cestroideae and perhaps Cestroideae is primitive in Solanaceae, and that Browallia seems more closely allied with the large, widespread genus Cestrum. Morphological evidence, analyzed phylogenetically and using multivariate techniques, implies that there are five species of Browallia. The generic boundaries of Browallia and the monotypic sister group Streptosolen jamesonii (Bentham) Miers are doubtful. Streptosolen, erected out of Browallia in 1850, is here resubmerged. The species recognized are Browallia acutiloba Segástegui & Díos, B. americana Linnaeus, B. eludens R. K. Van Devender & P. Jenkins, B. jamesonii Bentham, and B. speciosa Hooker. Four Browallia have limited distributions: three in the South American Andes and one disjunct in southwestern North America. The fifth, Browallia americana, is widespread and introduced throughout the tropics of the New and Old Worlds. It exhibits variable characters in the Andes of Peru, but less so elsewhere, especially where it is likely introduced. Morphological evidence suggests that the origin of the group is Andean, and that the genus is diverging, but that diversification does not warrant recognition of all the species previously described. Browallia eludens, with its disjunct range, poses interesting questions about the biogeographical history of the group. It has a more northern range where seasonally freezing temperatures occur. It appears to be a seasonal ephemeral with larger seeds than the tropical Browallia, that the seeds are viable for a number of years, and that the plants may be largely autogamous.

Key words: Browallia, phylogenetics, Solanaceae