Vernonia

Family Asterales. Order Asterales.

Large trees to small trees. Buttresses present, or absent; short. Spines absent. Stilt roots absent. Bark gray, brown; not peeling in strips. Slash cream, orange, 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; sparse.

Leaves spiral; 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; net like to 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 absent. Domatia absent. Basal glands absent. Hairs on mature leaf present; sparse.

Inflorescences present; terminal; on a branched axis; specialized inflorescence units present; specialized inflorescence units heads; numerous and persistent inflorescence bracts present at the bottom of the inflorescence. Flowers bisexual; 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 100 (appearing as a pappus of hairs); free; persistent in fruit; not growing any further 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 by the base; not awned; dehiscing by long slits. Ovary inferior. Carpels joined; 2. Locules 1. Styles solitary. Stigmas 2 lobed; not distinctive. Fruit an achene; non-fleshy; not multiple; not splitting; not enclosed in, or sitting on, fleshy perianth parts; wingless. Seeds 1 per fruit; barely visible, or less than 5 mm; wingless; uniform in cross-section; aril absent; non-endospermic.

Only tree of the Asteraceae in region. Taxon images: vernonia.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.