Osmoxylon Miq.

Unarmed, glabrous or tomentose shrubs or trees. Leaves palmately lobed or simple, rarely digitately compound; stipules forming a ligule, and the base of the petiole furnished with one to several spiral or transversal crests or collars (very rarely absent). Inflorescence a terminal compound umbel; peduncle short; primary rays each terminating into three branches; the central branch bearing a head or umbellule of almost always sterile bacciform flowers ('pseudo-fruits'); the two lateral branches each bearing a head or umbellule of hermaphrodite flowers. Calyx an obsolete rim or 0. Corolla with few to many lobes above, tubular below. Stamens 4-30, filaments thick, anthers oblong, exserted. Ovary inferior, not articulated with the pedicel, cells 1-many; disk flat with a central raised boss bearing the pustulate stigmas. Fruit subglobose (ribbed when dry); exocarp fleshy, endocarp crustaceous. Seeds compressed, endosperm smooth or wrinkled.

Mainly understorey trees in primary rain-forest, also in second growth forest, usually at low altitudes, especially in shaded situations and near rivers, 15. O. borneense a characteristic rheophyte.