Large trees to small trees. Buttresses absent. Spines absent. Stilt roots present, or absent. Bark green, red, brown, black; not peeling in strips. Slash red, brown. Vertical stripes in the inner bark or wood absent. Odor absent. Exudate present; red; flowing, or spotty; not blackening on exposure to air. Terminal buds not enclosed by leaves.
Complex hairs present, or absent; star-like. Stinging hairs absent. Mature twig indumentum absent.
Leaves two-ranked; not scale-like; simple; of different sorts on a single twig, or all of the same type; not modified into spines; coriaceous; gland-dotted, or not gland-dotted; symmetric at the base; not dissected; smooth margined. Epidermis waxy. Venation pinnate. Secondary veins open; prominent (& above). Smallest veins prominent; net like (tight), or 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; axillary, or on the trunk or branches; the flowers from a single point on the stem, or on a branched axis; specialized inflorescence units absent; numerous and persistent inflorescence bracts absent. Flowers at least some flowers unisexual; with male and female flowers on the same plant, or with male and female flowers on different plants; stalked; with the parts barely visible to the eye, or about 0.5 cm long or across; round; with male or female parts not raised on a column. Hypanthium absent. Disk absent. Perianth present; with all whorls looking like tepals. Tepals 3. Stamens 3-20(-100) (many); filaments present; joined; free of the perianth; all equal in size; isomerous, or diplostemonous, or triplostemonous, or polystemonous, or number of stamens not a multiple of the adjacent perianth whorl. Anthers 2 loculed; not awned; dehiscing by long slits. Ovary superior. Carpels solitary; 1. Locules 1. Styles solitary. Stigmas 1 lobed; not distinctive. Fruit follicular; fleshy; not multiple; splitting; not enclosed in, or sitting on, fleshy perianth parts; wingless. Seeds 1 per fruit; about 1 cm long, or much more than 1 cm long; wingless; with folds like marble, in cross- section; aril present (entire); endospermic.
Bark smooth to scaly; tertiary veins forming a close network and visible; flowers on knobs of wood; anthers free; aril divided at apex only. Taxon images: genknema.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.