Psydrax

Family Rubiaceae. Order Rubiales.

Large trees to small trees. Buttresses absent. Spines absent. Stilt roots absent. Bark gray, brown; not peeling in strips. Slash yellow, brown. Vertical stripes in the inner bark or wood absent. Odor absent. 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 to leathery; 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 not prominent, but visible to not visible; net like to ladder 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 to small; not persistent. Domatia present, or absent; pit-like; scattered along midrib, or scattered across lamina. Basal glands absent. Hairs on mature leaf present, or absent; dense, or sparse.

Inflorescences present; axillary; on an unbranched axis, or on a branched axis; specialized inflorescence units present, or absent; specialized inflorescence units umbels; 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 (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 1 lobed; distinctive; cylindrical. Fruit drupaceous; fleshy; not multiple; not splitting; not enclosed in, or sitting on, fleshy perianth parts; wingless. Seeds 2 per fruit; less than 5 mm; wingless; uniform in cross-section; aril absent; endospermic.

Anthers dorsifixed and inserted at top or corolla; stigma cylindrical; seeds with a wart-like texture. Taxon images: psydrax.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.