As currently circumscribed, the legume genus Enterolobium comprises 11 species in two sections: E. sect. Enterolobium and E. sect. Robrichia, with an overall distribution from Mexico to Argentina and a centre of diversity in Amazonia. In the absence of the characteristic indehiscent fruits, Enterolobium is difficult to distinguish from other genera in the ingoid clade, including Albizia sensu lato, Samanea, and Cathormion. Previous phylogenetic studies which have included Enterolobium have sampled few species of the genus, leaving questions about its monophyly and interspecific relationships. Here we evaluate the circumscription of Enterolobium and its two infrageneric taxa, their phylogenetic placement in the ingoid clade, and interspecific relationships within the two sections of the genus. Our study includes all Enterolobium species, and analyses of nuclear (ITS and ETS) and plastid (trnD-T and trnL-F) molecular regions, and morphology. Bayesian inference, maximum parsimony, and maximum likelihood analyses show that Enterolobium, as presently circumscribed, is not monophyletic. The genus is divided into two well-supported independent clades, corresponding to the two previously recognized sections; one of them is sister to the genus Leucochloron and is here raised to generic rank as the genus Robrichia, with three species, Robrichia glaziovii, Robrichia oldemanii and Robrichia schomburgkii. The genus Enterolobium consequently now comprises eight species and is more closely related to a clade composed of Albizia and Falcataria. This new arrangement is reinforced by morphological synapomorphies recovered by ancestral character state reconstructions. Indumentum type, the number of pinnae pairs per bipinnate leaf and leaflet pairs per pinna, inflorescence type, and fruit shape characterize Robrichia, while the recognition of Enterolobium remains based on fruit traits. We also provide the formal lectotypifications for E. contortisiliquum, E. cyclocarpum, E. gummiferum, E. maximum, E. monjollo, and R. schomburgkii.