The Lythraceae are a family of 31 genera of world-wide distribution growing primarily in wet to moist habitats of the subtropics and tropics. The family is represented in the Antilles by seven genera and 39 species. Two genera, Ginoria and Haitia, and 21 species are endemic to the islands of the Caribbean. Ginoria with 14 species and Cuphea with 10-15 species are best represented. Cladistic analyses place Ginoria in an Afro-Asian clade as sister to Tetrataxis of Madagascar. The ancestral route of dispersion to the Caribbean is not clear, although a basal member of the clade, Lawsonia, is known from the Middle Eocene of British Columbia, suggesting an ancestral boreotropical route. The center of origin for Cuphea is most likely eastern South America. Cuphea has dispersed into the Greater Antilles from Brazil a minimum of five times and into the Lesser Antilles from northeastern South America twice. Lythrum and Heimia have moved to the Antilles from North America. For Rotala and Ammannia, a boreotropical dispersion route from Asia through North America to the Caribbean, or oceanic dispersal of seeds from Africa is equally likely. Seeds of all Antillean Lythraceae are minute in size and have floats or mucilaginous hairs that enhance chances of long distance dispersal by wind and water. Vicariance, although it may have occurred, is not required to explain the distribution of Lythraceae in the Antilles.

Key words: Antilles, biogeography, Cuphea, dispersal, Ginoria, Lythraceae