Large trees. Buttresses absent. Spines absent. Stilt roots absent. Bark gray, brown; not peeling in strips. Slash brown. Vertical stripes in the inner bark or wood absent. Odor absent. Exudate present, or absent; 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 spiral; not scale-like; simple; all of the same type; not modified into spines; coriaceous; not gland-dotted; symmetric at the base; not dissected; smooth margined. Epidermis not waxy. Venation pinnate. Secondary veins open; prominent. Smallest veins not prominent, but visible; ladder like. Intramarginal vein absent. Stalk of blade a quarter to one half the length of the blade to more than half the length of the blade; not winged; attached to base of leaf blade; swollen; swollen at one end. Stipules present; free from one another; laterally placed; not encircling the twig; scale-like; not fringed; small; not persistent. Domatia absent. Basal glands present. Hairs on mature leaf absent.
Inflorescences present; terminal, or axillary; 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; stalked; 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 (4-)5(-6); free; not persistent in fruit; not growing any further after flowering. Epicalyx absent. Petals absent. Stamens 10-20(-100) (many); filaments present; free of each other; free of the perianth; all equal in size; diplostemonous, or triplostemonous, or polystemonous. Anthers 2 loculed; attached by the base; not awned; dehiscing by long slits. Ovary superior. Carpels joined; (2-)3(-4). Locules 2-4. Styles solitary. Stigmas 3 lobed; not distinctive. Fruit capsular; non-fleshy; not multiple; splitting; not enclosed in, or sitting on, fleshy perianth parts; wingless. Seeds 3 per fruit; much more than 1 cm long; wingless; uniform in cross-section; aril absent; endospermic.
Petiole long and kneed apically; fruit a large woody capsule. Taxon images: elaterio.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.