Stemonurus

Family Icacinaceae. Order Celastrales.

Large trees to shrubs. Buttresses present, or absent; short. Spines absent. Stilt roots present, or absent. Bark gray, brown; not peeling in strips. Slash yellow, green, orange. Vertical stripes in the inner bark or wood absent. Odor absent. 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; leathery; not gland-dotted; symmetric at the base; not dissected; smooth margined. Epidermis not waxy. Venation pinnate. Secondary veins open; prominent. Smallest veins not prominent, but visible, or 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 absent. Domatia absent. Basal glands absent. Hairs on mature leaf absent.

Inflorescences present; axillary; on an unbranched axis; specialized inflorescence units present; specialized inflorescence units umbels; 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 present; the stamens outside the disk. Perianth present; with distinct calyx and corolla whorls. Sepals 5; partially joined; persistent in fruit; not growing any further after flowering. Epicalyx absent. Petals present; (4-)5; all joined (base); not fleshy; deciduous; not stalked; entire. Stamens (4-)5; filaments present; free of each other; free of the perianth; all equal in size; isomerous; opposite the sepals (when isomerous). Anthers 2 loculed; attached along the side; not awned; dehiscing by long slits. Ovary superior. Carpels joined. Locules 1. Styles solitary. Stigmas 1 lobed; not distinctive. Fruit drupaceous; fleshy; not multiple; not splitting; not enclosed in, or sitting on, fleshy perianth parts; wingless. Seeds 1 per fruit; less than 5 mm to about 1 cm long; wingless; uniform in cross-section; aril absent; endospermic.

Trees, sometimes with buttresses and/or pneumatophores; inflorescences umbellate, sometimes with persistent bracts; stamens with long hairs below the anthers. Taxon images: genstem.gif stemon.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.