Because systematists are usually more familiar with some geographical areas than others, relationships associated with intercontinental disjunctions can be overlooked. The relationship between the mostly neotropical Caricaceae and the paleotropical Moringaceae is presented as an example. The sister taxon relationship between these families, and indeed their mutual presence in Brassicales, was not recognized until recent molecular phylogenetic studies. Yet numerous morphological similarities were uncovered between the families in recent studies. These characters, which may be synapomorphies of the Caricaceae-Moringaceae clade, include grooved glands on the lamina and stipules, and the pachycaul tree life form. Other characters, such as pith hollowings, have different ontogenetic origins and may be non-homologous or may be higher-level characters. The implications of phylogeny reconstruction within the Caricaceae-Moringaceae clade with regard to distribution is discussed, particularly with reference to other taxa with a northeast Africa-Mesoamerica disjunction. The three genera of neotropical Caricaceae form a clade that is sister to the African Cylicomorpha, the only other genus in the family. Moringaceae is characterized by a basal paraphyletic assemblage of African and Malagasy species, with the rest of the family falling into a northeast African clade and a southern Asian clade. Phylogenetic reconstructions suggest a single origin of Caricaceae in the New World, with subsequent diversification, particularly in Mexico and northwest South America, as opposed to repeated dispersal to the neotropics.

Key words: Africa-Mesoamerica disjunction, anatomy, Brassicales, Caricaceae, Moringaceae