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Phylogenetics of Chilopsis and Catalpa (Bignoniaceae) was elucidated based on sequences of chloroplast ndhF and the nrDNA ITS region. In Bignoniaceae, Chilopsis and Catalpa are most closely related as sister genera. Our data supported section Macrocatalpa of the West Indies and section Catalpa of eastern Asian and North American continents. Within section Catalpa, Catalpa ovata of eastern Asia form a clade with North American species, C. speciosa and C. bignonioides, while the other eastern Asian species comprise a clade where C. duclouxii is sister to the clade of C. bungei and C. fargesii. The Caribbean species of Catalpa diverged early from the continental species. More studies are needed to test whether the phylogenetic pattern is common in eastern Asian-North American disjunct genera with species in the West Indies.