Rennellia

Family Rubiaceae. Order Rubiales.

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

Complex hairs absent. Stinging hairs absent. Mature twig indumentum absent.

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 to not prominent, but visible. Smallest veins prominent to not visible; net like. Intramarginal vein present, or 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; persistent. Domatia absent. Basal glands absent. Hairs on mature leaf present, or absent; dense, or sparse.

Inflorescences present; terminal; on an unbranched axis; specialized inflorescence units present; specialized inflorescence units heads; numerous and persistent inflorescence bracts absent. Flowers at least some flowers unisexual; with male and female flowers on different plants; not stalked; 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 4-5; partially joined; not persistent in fruit; not growing any further after flowering. Epicalyx absent. Petals present; 4-5; all joined; not fleshy; deciduous; not stalked; entire. Stamens 4-5; filaments present; free of each other; joined to 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 inferior. Carpels joined; 2. Locules 2. Styles solitary. Stigmas 2 lobed; not distinctive. Fruit berry-like; fleshy; multiple; not splitting; not enclosed in, or sitting on, fleshy perianth parts; wingless. Seeds 100 per fruit; less than 5 mm; wingless; uniform in cross-section; aril absent; endospermic.

Stipules split at the apex; inflorescence comprised of heads along an unbranched rachis.


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.