The Buddlejaceae sensu stricto is a small group of plants which recent evidence has shown to consist of four genera. The genus Buddleia is the largest and most widely distributed genus, consisting of approximately 100 species distributed in Asia, Africa, and the Americas. Emorya, Gomphostigma, and Nicodemia, each mono- or ditypic genera, are more geographically restricted. Sequences from 28 ingroup and seven outgroup taxa were examined in a phylogenetic analysis of the trnL intron and trnL-F intergenic spacer region of the chloroplast DNA to test monophyly of the ingroup and to determine relationships among Buddleia and related genera. Parsimony analyses result in two major clades with modest support. One clade consists primarily of Asian species of Buddleia and the segregate genera. The sister clade is composed of New World and South African species of Buddleia. High bootstrap values support the close relationships among the four genera, but our data do not support recognition of Emorya, Gomphostigma, and Nicodemia as separate genera. Traditional sectional treatments of Buddleia, based primarily on floral morphological characters, are well supported. The two species of Nicodemia, often regarded as a section within Buddleia based upon its fleshy fruits, are shown to be closely related. Other interspecific relationships are poorly supported or unresolved.

Key words: Buddleia, Buddlejaceae, trnL