Argusia

Family Boraginaceae. Order Lamiales.

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; dense.

Leaves spiral; 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, or wavy margined, or with small to large teeth on margin. Epidermis not waxy. Venation pinnate. Secondary veins open; not prominent, but visible. Smallest veins not prominent, but visible; net 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 absent. Domatia absent. Basal glands absent. Hairs on mature leaf present; dense.

Inflorescences present; terminal; on a branched axis; specialized inflorescence units absent; numerous and persistent inflorescence bracts absent. Flowers bisexual; not stalked, or stalked; about 0.5 cm long or across; round; with male or female parts not raised on a column. Hypanthium absent. Disk absent. Perianth present; with distinct calyx and corolla whorls. Sepals 5; partially joined; persistent in fruit; not growing any further after flowering, or growing slightly after flowering. Epicalyx absent. Petals present; 5; all joined; not fleshy; deciduous; not stalked; entire. Stamens 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 superior. Carpels joined; 2. Styles absent. Stigmas 2 lobed; not distinctive. Fruit drupaceous; non-fleshy; not multiple; splitting; not enclosed in, or sitting on, fleshy perianth parts; wingless. Seeds 4 per fruit; less than 5 mm; wingless; uniform in cross-section; aril absent; non-endospermic.

Leaves and young twigs covered in dense silver-colored hairs; stigma sessile and bilobed. Taxon images: argusia.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.