Dimorphocalyx

Family Euphorbiaceae. Order Euphorbiales.

Small trees to shrubs. Buttresses absent. Spines absent. Stilt roots absent. Bark gray, brown; not peeling in strips. Exudate absent. 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 to leathery; not gland-dotted; symmetric at the base; not dissected; smooth margined, or with small to large teeth on margin. Epidermis waxy, or not waxy. Venation pinnate. Secondary veins open; prominent to not prominent, but visible. Smallest veins not prominent, but visible to not visible; net like. Intramarginal vein present. Stalk of blade less than a quarter the length of the blade; not winged; attached to base of leaf blade; not swollen. Stipules present; free from one another; laterally placed; not encircling the twig; scale-like; not fringed; small; not persistent. Domatia absent. Basal glands absent. Hairs on mature leaf absent.

Inflorescences present; axillary; on an unbranched 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 absent. Perianth present; with distinct calyx and corolla whorls. Sepals 5; free; persistent in fruit; growing slightly after flowering. Epicalyx absent. Petals present; 5; free; fleshy; deciduous; not stalked; entire. Stamens 10-20(-100) (many); filaments present; joined; free of the perianth; all equal in size; polystemonous. Anthers 2 loculed; attached along the side; not awned; dehiscing by long slits. Ovary superior. Carpels joined; 3. Locules 3. Styles solitary. Stigmas 6 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; uniform in cross-section; aril absent; endospermic.

Fruits sit on an enlarged calyx; stamens 10-20 with the inner ones fused into a column. Taxon images: dimorpho.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.