Macaranga

Family Euphorbiaceae. Order Euphorbiales.

Large trees to small trees. Buttresses present, or absent; short. Spines absent. Stilt roots absent. Bark gray; not peeling in strips. Slash cream. Vertical stripes in the inner bark or wood absent. Odor absent. Exudate present, or absent; red; flowing, or spotty; not blackening on exposure to air. Terminal buds not enclosed by leaves.

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

Leaves spiral; not scale-like; simple; all of the same type; not modified into spines; coriaceous, or leathery; gland-dotted, or not gland-dotted; symmetric at the base; dissected, or not dissected; palmately lobed; smooth margined, or wavy margined, or with small to large teeth on margin. Epidermis waxy, or not waxy. Venation trinerved, or palmate. Secondary veins open; prominent. Smallest veins prominent, or not prominent, but visible; net like, or 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 surface of leaf blade, attached to base of leaf blade; swollen; swollen at one end, or swollen at both ends. Stipules present; free from one another; laterally placed; encircling the twig, or not encircling the twig; leafy; not fringed; large, or small; not persistent, or persistent. Domatia absent. Basal glands present, or absent. Hairs on mature leaf present, or absent; dense, or sparse.

Inflorescences present; axillary, or leaf-opposed; on an unbranched axis, or 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 different plants; 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 2-5; free; not persistent in fruit; not growing any further after flowering. Epicalyx absent. Petals absent. Stamens (1-)2-100 (many); filaments present; free of each other; free of the perianth; all equal in size; anisomerous, or isomerous, or diplostemonous, or triplostemonous, or polystemonous; alternating with the sepals (when isomerous). Anthers 3-4 loculed; attached by the base; not awned; dehiscing by long slits. Ovary superior. Carpels joined; 2-3. Locules (1-)2-3(-6). Styles free; 2-3. Stigmas 1 lobed; not distinctive. Fruit capsular; non-fleshy; not multiple; splitting; not enclosed in, or sitting on, fleshy perianth parts; winged, or wingless. Seeds 2-3 per fruit; less than 5 mm; wingless; uniform in cross-section; aril present, or aril absent; endospermic.

Twigs hollow and full of ants; stipules large and persistent; petiole long and kneed; tertiary veins ladder-like; fruits waxy. Taxon images: genmacar.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.