Small trees to shrubs. Buttresses absent. Spines absent. Stilt roots absent. Bark brown; not peeling in strips. Exudate absent. Terminal buds not enclosed by leaves.
Complex hairs absent. Stinging hairs absent. Mature twig indumentum absent.
Leaves whorled, or spiral; 3-5 per whorl; 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, or not prominent, but visible. Smallest veins prominent, or not prominent, but visible; net 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 absent.
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, or intergrading from sepals to petals. Sepals 5; free, or partially joined; persistent in fruit; not growing any further after flowering. Epicalyx absent. Petals present; 5; all joined (at base); not fleshy; deciduous; not stalked; entire. Stamens 100 (many); filaments present; joined, or free of each other; all equal in size; polystemonous. Anthers 2 loculed; attached by the base; not awned; dehiscing by long slits. Ovary superior. Carpels joined; 3-5. Locules 3-5. Styles solitary, or free; 3-5. Stigmas 1-5 lobed (1 or 3-5); not distinctive. Fruit capsular, or drupaceous; fleshy, or non-fleshy; not multiple; splitting, or not splitting; not enclosed in, or sitting on, fleshy perianth parts; wingless. Seeds 5-30 per fruit; less than 5 mm; wingless; uniform in cross-section; aril absent; non-endospermic.
Flowers axillary and solitary. Taxon images: genpyren.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.