Large trees to shrubs. Buttresses absent. Spines absent. Stilt roots absent. Bark gray; not peeling in strips. Slash cream. Vertical stripes in the inner bark or wood absent. Odor absent. Exudate present; white; flowing; not blackening on exposure to air. Terminal buds not enclosed by leaves.
Complex hairs absent. Stinging hairs absent. Mature twig indumentum absent.
Leaves opposite; not scale-like; simple; all of the same type; not modified into spines; coriaceous, or leathery, or fleshy; not gland-dotted; symmetric at the base; not dissected; smooth margined. Epidermis not waxy. Venation pinnate. Secondary veins open; prominent, or not prominent, but visible. Smallest veins not prominent, but visible, or not visible; net like. Intramarginal vein present, or absent. Stalk of blade less than a quarter the length of the blade; not winged; attached to base of leaf blade; not swollen, or swollen; swollen at one end. Stipules absent. Domatia absent. Basal glands absent. Hairs on mature leaf absent.
Inflorescences present; terminal, or axillary; on an unbranched axis, or on a branched axis; specialized inflorescence units absent; numerous and persistent inflorescence bracts absent. Flowers bisexual; stalked; about 0.5 cm long or across, or to about 3 cm long or across; round; with male or female parts not raised on a column. Hypanthium absent. Disk present; the stamens outside the disk. Perianth present; with distinct calyx and corolla whorls. Sepals 5; partially joined; not persistent in fruit; not growing any further after flowering. Epicalyx absent. Petals present; 5; all joined; not fleshy; deciduous; not stalked; entire. Stamens 5; filaments present; free of each other; joined to the perianth; all equal in size; isomerous; opposite the sepals (when isomerous). Anthers 2 loculed; attached by the base; not awned; dehiscing by long slits. Ovary superior. Carpels partially joined, by styles; 2. Locules 1. Styles solitary. Stigmas 1 lobed; distinctive; head shaped. Fruit follicular; fleshy; not multiple; splitting; not enclosed in, or sitting on, fleshy perianth parts; wingless. Seeds 100 per fruit (many); barely visible; wingless; uniform in cross-section; aril absent; endospermic.
Copious white latex from slash; leaves with a swollen base; fruits fleshy, orange to red. Taxon images: gentaber.gif
Cite this publication as: Jarvie, J.K. and
Ermayanti (1996 onwards). `Tree Genera of Borneo - Descriptions and
Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993) should also be cited.