Praravinia

Family Rubiaceae. Order Rubiales.

Small trees to shrubs. Buttresses absent. Spines absent. Stilt roots absent. Bark brown; 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 opposite; 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 prominent to not prominent, but visible; net like, or ladder like. Intramarginal vein absent. Stalk of blade less than a quarter the length of the blade; not winged; attached to base of leaf blade; not swollen. Stipules present; joined; joined across twigs; encircling the twig; leafy; not fringed; large; not persistent. Domatia absent. Basal glands absent. Hairs on mature leaf present, or absent; dense, or sparse.

Inflorescences present, or represented by solitary flowers only; axillary, or on the trunk or branches; the flowers from a single point on the stem, 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; with the parts barely visible to the eye to about 0.5 cm long or across; round; with male or female parts not raised on a column. Hypanthium absent. Disk present. Perianth present; with distinct calyx and corolla whorls. Sepals (3-)4(-6); partially joined; persistent in fruit, or not persistent in fruit; not growing any further after flowering. Epicalyx absent. Petals present; 5-12; all joined; not fleshy; deciduous; not stalked; entire. Stamens 8-12; filaments present; free of each other; joined to the perianth; all equal in size; diplostemonous. Anthers 2 loculed; attached by the base; not awned; dehiscing by long slits. Ovary superior. Carpels joined; 5-16. Locules 5-16. Styles solitary. Stigmas 1 lobed; not distinctive. Fruit berry-like; fleshy; not multiple; not splitting; not enclosed in, or sitting on, fleshy perianth parts; wingless. Seeds 100 per fruit (many); barely visible; wingless; uniform in cross-section; aril absent; endospermic.

Flowers unisexual; stamen number exceeds corolla lobe number. Taxon images: prarivan.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.