Large trees to shrubs. Buttresses present, or absent; short. Spines present, or absent (Alangium salvifolium). Stilt roots present, or absent. Bark white, cream, red, gray, brown; not peeling in strips. Slash yellow, orange, red, brown. Vertical stripes in the inner bark or wood absent. Odor absent. Exudate absent. Terminal buds not enclosed by leaves.
Complex hairs present, or absent; star-like. Stinging hairs absent. Mature twig indumentum present, or absent; dense, or sparse.
Leaves spiral, or two-ranked; not scale-like; simple; all of the same type; not modified into spines; coriaceous, or paper-like; not gland-dotted; very asymmetric at the base, or symmetric at the base; not dissected; smooth margined. Epidermis not waxy. Venation pinnate, or trinerved, or palmate. Secondary veins open; prominent. Smallest veins prominent, or not prominent, but visible; ladder like. Intramarginal vein present, or absent. Stalk of blade less than a quarter the length of the blade to a quarter to one half the length of the blade; not winged; attached to base of leaf blade; not swollen, or swollen; swollen at one end. Stipules absent. Domatia present, or absent; pit-like; scattered along midrib. Basal glands absent. Hairs on mature leaf present, or absent; dense, or sparse.
Inflorescences present; axillary; on an unbranched axis, or on a branched axis; specialized inflorescence units absent; numerous and persistent inflorescence bracts absent. Flowers bisexual; not stalked, or 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 4-10; partially joined; persistent in fruit; not growing any further after flowering. Epicalyx absent. Petals present; 4-10; free; not fleshy; deciduous; not stalked; entire. Stamens 4-10(-100) (many); filaments present; free of each other; free of the perianth; all equal in size; isomerous to polystemonous; opposite the sepals (when isomerous). Anthers 2 loculed; attached by the base; not awned; dehiscing by short slits, or dehiscing by long slits. Ovary inferior. Carpels solitary, or joined; 1-2. Locules 1-2. Styles solitary. Stigmas 1 lobed; not distinctive. Fruit drupaceous; fleshy; not multiple; not splitting; not enclosed in, or sitting on, fleshy perianth parts; wingless. Seeds 1-2 per fruit; less than 5 mm, or about 1 cm long; wingless; uniform in cross-section; aril absent; endospermic.
Secondary veins sometimes trinerved or otherwise palmate; tertiary veins almost perpendicular to midrib; fruit often longitudinally grooved. Taxon images: genalang.gif alang.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.