Large trees to small trees. Buttresses present, or absent; short. Spines absent. Stilt roots present, or absent. Bark gray, brown; peeling in strips. Slash cream. Vertical stripes in the inner bark or wood absent. Odor aromatic. Exudate absent. Terminal buds not enclosed by leaves.
Complex hairs absent. Stinging hairs absent. Mature twig indumentum present, or absent; dense, or sparse.
Leaves two-ranked; not scale-like; simple; all of the same type; not modified into spines; coriaceous, or leathery, or paper-like; gland-dotted, or not gland-dotted; symmetric at the base; not dissected; smooth margined. Epidermis waxy, or not waxy. Venation pinnate. Secondary veins open; prominent, or not prominent, but visible. Smallest veins not prominent, but visible, or not visible; ladder 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. Stipules absent. Domatia absent. Basal glands absent. Hairs on mature leaf present, or absent; dense, or sparse.
Inflorescences present, or represented by solitary flowers only; axillary; the flowers from a single point on the stem; 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 absent. Perianth present; with distinct calyx and corolla whorls. Sepals 3; free; not persistent in fruit; not growing any further after flowering. Epicalyx absent. Petals present; 6; free; fleshy; deciduous; not stalked; entire. Stamens 100 (many); filaments absent; free of the perianth; all equal in size; polystemonous. Anthers 2 loculed; not awned; dehiscing by short slits. Ovary superior. Carpels solitary, or separate; 1-100 (many). Locules 1. Styles solitary. Stigmas 1 lobed; not distinctive. Fruit follicular; fleshy; not multiple; splitting, or not splitting; not enclosed in, or sitting on, fleshy perianth parts; wingless. Seeds 2-10 per fruit; less than 5 mm, or about 1 cm long; wingless; with folds like marble, in cross- section; aril present; endospermic.
Large trees; sometimes buttressed; fruits splitting; aril blue. Taxon images: genxylop.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.