Large trees to small trees. Buttresses absent. Spines absent. Stilt roots present. Bark gray, brown; not peeling in strips. Slash orange, red, gray, brown. Vertical stripes in the inner bark or wood absent. Odor absent. Exudate present, or absent; white; spotty; not blackening on exposure to air. Terminal buds not enclosed by leaves.
Complex hairs present, or absent; T-shaped. Stinging hairs absent. Mature twig indumentum present, or absent; dense, or sparse.
Leaves opposite, or spiral; 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 not waxy. Venation pinnate. Secondary veins open; prominent. Smallest veins not prominent, but visible; net like, or ladder 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. Stipules absent. Domatia present, or absent. Basal glands absent. Hairs on mature leaf present, or absent; dense, or sparse.
Inflorescences present; terminal, or axillary; on a branched axis; specialized inflorescence units present; specialized inflorescence units heads; 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 4-5(-7); partially joined; persistent in fruit; not growing any further after flowering. Epicalyx absent. Petals present; 4-5(-6); free; fleshy, or not fleshy; deciduous; not stalked; lobed, or fringed like a comb, or entire. Stamens 4-5(-6), or 8; filaments present; free of each other; free of the perianth; all equal in size; isomerous, or diplostemonous; opposite the sepals (when isomerous). Anthers 2 loculed; attached along the side; not awned; dehiscing by long slits. Ovary inferior. Carpels joined; 4-5. Locules 1. Styles solitary. Stigmas 1-5 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.
Slash sometimes white resinous; ovary inferior; prominent disk; style sometimes bifid; fruit dark blue or purple, calyx persistent. Taxon images: genmasti.gif mastixia.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.