Large trees to small trees. Buttresses absent. Spines absent. Stilt roots absent. Bark gray, brown; not peeling in strips. Slash yellow. Vertical stripes in the inner bark or wood absent. Odor absent. Exudate absent. 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 paper-like; not gland-dotted; symmetric at the base; not dissected; smooth margined. Epidermis not waxy. Venation pinnate. Secondary veins open; prominent to not prominent, but visible. Smallest veins not prominent, but visible to not visible; ladder like. Intramarginal vein absent. Stalk of blade less than a quarter the length of the blade; not winged; attached to base of leaf blade; not swollen. Stipules present; free from one another; joined across twigs; encircling the twig; leafy; not fringed; large; not persistent, or persistent. Domatia absent. Basal glands absent. Hairs on mature leaf present, or absent; sparse.
Inflorescences present; terminal; on an unbranched axis; specialized inflorescence units present; specialized inflorescence units heads; numerous and persistent inflorescence bracts absent. Flowers bisexual; stalked; with the parts barely visible to the eye to about 0.5 cm long or across; round; with male or female parts not raised on a column. Hypanthium absent. Disk present. Perianth present; with distinct calyx and corolla whorls. Sepals 5; partially joined; 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 along the side; not awned; dehiscing by long slits. Ovary superior. Carpels joined; 2. Locules 2. Styles solitary. Stigmas 1 lobed; not distinctive. Fruit capsular; non-fleshy; multiple; splitting; not enclosed in, or sitting on, fleshy perianth parts; wingless. Seeds 100 per fruit (many); barely visible; winged; uniform in cross-section; aril absent; endospermic.
Stipules generally persistent, with obvious lateral keels; fruits breaking free of the head, densely hairy.
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.