Handroanthus

Handroanthus is a genus of flowering plants in the family Bignoniaceae. It consists of 30 species of trees, known in Latin America by the common names poui, pau d'arco, or ipê. The latter sometimes appears as epay or simply ipe (unaccented) in English. The large timber species are sometimes called lapacho or guayacan, but these names are more properly applied to the species Handroanthus lapacho and Handroanthus guayacan, respectively. The name Handroanthus was established in 1970, but was not generally accepted. In 1992, its species were included in Tabebuia in the most recent revision of that genus. Handroanthus was resurrected in 2007 when a comparison of DNA sequences by cladistic methods showed that Tabebuia, as then circumscribed, was not monophyletic. Handroanthus are indigenous from Central America to northern Argentina, Paraguay, Brazil, and Chile, with one species, Handroanthus billbergii, native to northern South America and the Antilles. Handroanthus are frequently cultivated far from their natural range, as ornamental trees, for their large and showy flowers. They easily become naturalized where introduced because their seeds are prolifically produced and widely scattered by the wind. Several species are important timber trees of the American tropics. Medicinal use has been reported, but its efficacy and side effects have not been well studied.