Tristaniopsis

Family Myrtaceae. Order Myrtales.

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

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

Leaves spiral; not scale-like; simple; all of the same type; not modified into spines; coriaceous; gland-dotted; symmetric at the base; not dissected; smooth margined. Epidermis not waxy. Venation pinnate. Secondary veins closed; prominent, or not prominent, but visible. Smallest veins prominent, or not prominent, but 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 present, or absent; sparse.

Inflorescences present; axillary; on a branched axis; specialized inflorescence units absent; numerous and persistent inflorescence bracts absent. Flowers bisexual; stalked; about 0.5 cm long or across to to about 3 cm long or across; round; with male or female parts not raised on a column. Hypanthium present. Disk absent. Perianth present; with distinct calyx and corolla whorls. Sepals 5; free, or partially joined; not persistent in fruit; not growing any further after flowering. Epicalyx absent. Petals present; 5; free; not fleshy; deciduous; not stalked; entire. Stamens 15-25(-100) (many); filaments present; joined; free of the perianth; all equal in size; triplostemonous, or polystemonous. Anthers 2 loculed; attached along the side; not awned; dehiscing by long slits. Ovary partly inferior. Carpels joined; 3. Locules 3. Styles solitary. Stigmas 1 lobed; not distinctive. Fruit capsular; non-fleshy; not multiple; splitting; not enclosed in, or sitting on, fleshy perianth parts; wingless. Seeds 100 per fruit (many); less than 5 mm; winged; uniform in cross-section; aril absent; non-endospermic.

Bark orange to brown and scrolling; leaves spiral at found at twig ends, gland dotted; veins numerous and close set. Taxon images: trist.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.