Small trees. Buttresses absent. Spines absent. Stilt roots absent. Bark gray, brown; not peeling in strips. Exudate absent. Terminal buds not enclosed by leaves.
Complex hairs present; star-like. Stinging hairs absent. Mature twig indumentum present, or absent; dense, or sparse.
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; with small to large teeth on margin (sometimes glandular). Epidermis not waxy. Venation pinnate. Secondary veins open; prominent. Smallest veins prominent, or not prominent, but visible; ladder like. Intramarginal vein 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; dense, or sparse.
Inflorescences present; terminal; on an unbranched axis; specialized inflorescence units absent; numerous and persistent inflorescence bracts absent. Flowers bisexual; stalked; 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 distinct calyx and corolla whorls. Sepals 5(-6); partially joined; persistent in fruit; not growing any further after flowering. Epicalyx absent. Petals present; 5(-6); free; not fleshy; deciduous; not stalked; lobed, or entire. Stamens 10(-12); filaments present; free of each other; joined to the perianth (at base); all equal in size; diplostemonous. Anthers 2 loculed; attached along the side; not awned; dehiscing by pores. Ovary superior. Carpels joined; 3. Locules 3. 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 100 per fruit (many); barely visible, or less than 5 mm; wingless; uniform in cross-section; aril absent; endospermic.
Leaves serrate with stellate hairs; anthers opening by pores; ovary 3-chambered. Taxon images: clethraz.gif clethra2.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.