Monoecious, with lateral (rarely also terminal) cymose inflorescences, much shorter than the leaves. Shrubs or small trees. Leaves pubescent or glabrous at maturity, entire or dentate. Stamens 4, free;
Anambas Is: present Asia-Tropical:, Borneo present; Malaya (Peninsular Malaysia present); Philippines (Philippines present); Sulawesi (Sulawesi present); Sumatera (Sumatera present) N. Moluccas: present Talaud Is: present
Malesia: Malay Peninsula, Sumatra, Anambas Is., Borneo, Celebes, Philippines, N. Moluccas (Talaud Is.).
The distinction between Matthaea and Steganthera is very slight. The two genera are so alike vegetatively that sterile specimens cannot be allocated to a genus with confidence, and their flowers and fruits are also very similar except for their anthers. In both genera there are four stamens; in Matthaea these bear anthers opening by two more or less vertical slits, whereas in Steganthera the anthers open by a single horizontal slit. It is useful to maintain the two genera because they are geographically separated (though both may occur in Celebes). Matthaea is restricted to western Malesia while Steganthera, a considerably larger genus, is centered on New Guinea with outliers in the Moluccas, Celebes and Queensland. Some uncertainties of range remain as male flowers and fruits are not available from several areas.