Lasianthus

Family Rubiaceae. Order Rubiales.

Small trees to shrubs. Buttresses absent. Spines absent. Stilt roots absent. Bark 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, or not prominent, but visible; 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.

Inflorescences present; axillary; the flowers from a single point on the stem, or on an unbranched axis, or on a branched axis; specialized inflorescence units absent; 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. Perianth present; with distinct calyx and corolla whorls. Sepals 3-5; partially joined; not persistent in fruit; not growing any further after flowering. Epicalyx absent. Petals present; 3-8; all joined; not fleshy; deciduous; not stalked; entire. Stamens 3-7; 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; 3-9. Locules 3-9. Styles solitary. Stigmas 3-9 lobed; not distinctive. Fruit drupaceous; fleshy; not multiple; not splitting; not enclosed in, or sitting on, fleshy perianth parts; wingless. Seeds 3 per fruit, or 9 per fruit; less than 5 mm; wingless; uniform in cross-section; aril absent; endospermic.

Leaves usually densely hairy and arranged to as to appear already pressed. Taxon images: lasianth.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.