Cleistanthus

Family Euphorbiaceae. Order Euphorbiales.

Small trees to shrubs. Buttresses absent. Spines absent. Stilt roots absent. Bark gray; not peeling in strips. Exudate absent. Terminal buds not enclosed by leaves.

Complex hairs present, or absent; disk-shaped. Stinging hairs absent. Mature twig indumentum present, or absent; dense, or sparse.

Leaves two-ranked; 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 waxy, or not waxy. Venation pinnate. Secondary veins open; prominent. 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 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 present; free from one another; laterally placed; not encircling the twig; scale-like; not fringed; small; not persistent, or persistent. Domatia absent. Basal glands absent. Hairs on mature leaf present, or absent; dense, or sparse.

Inflorescences present; axillary; the flowers from a single point on the stem; 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; with the parts barely visible to the eye; round; with male or female parts not raised on a column. Hypanthium absent. Disk present. Perianth present; with distinct calyx and corolla whorls. Sepals 5; free; not persistent in fruit; not growing any further after flowering. Epicalyx absent. Petals present; 5; free; not fleshy; deciduous; not stalked; entire. Stamens 5; filaments present; joined; free of the perianth; all equal in size; isomerous; alternating with the sepals (when isomerous). Anthers 2 loculed; attached by the base; not awned; dehiscing by long slits. Ovary superior. Carpels joined; (2-)3(-4). Locules 3. Styles solitary. Stigmas 2 lobed; not distinctive. Fruit capsular; non-fleshy; not multiple; splitting; not enclosed in, or sitting on, fleshy perianth parts; wingless. Seeds 6 per fruit; less than 5 mm; wingless; with folds like marble, in cross- section, or uniform in cross-section; aril absent; endospermic.

Like Bridelia, but the fruit a smooth, woody and dehiscent capsule and the base of the capsule remaining attached after dehiscence. Taxon images: cleistan.gif


Cite this publication as: Jarvie, J.K. and Ermayanti (1996 onwards). `Tree Genera of Borneo - Descriptions and Illustrations' URL http://django.harvard.edu/users/jjarvie/Borneo.htm/.
Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993) should also be cited.