Trees, unarmed. Leaves bipinnate; stipules not conspicuous; petiole with gland; pinnae and leaflets in numerous pairs. Heads globose, solitary or in racemes, axillary. Flowers dimorphic or uniform, bisexual. Calyx campanulate, shortly 5-dentate. Corolla fun­nel-shaped, 5-lobed. Stamens numerous, basally connate into a tube; anthers eglandular. Ovary sessile, many ovuled; style filiform. Legume broadly circinate or incurved-reniform, thick, hard, not dehiscent; mesocarp spongy, at length hardened. Seeds transverse, compressed, with pleurogram; funicle filiform.

Five species: tropical regions of the Americas; one species (introduced) in China.