Intsia

Family Fabaceae. Order Fabales.

Emergent trees to large trees. Buttresses present, or absent; tall. Spines absent. Stilt roots absent. Bark yellow, brown; not peeling in strips. Slash red, brown. Vertical stripes in the inner bark or wood absent. Odor absent. Exudate present, or absent; colorless; spotty; not blackening on exposure to air. Terminal buds not enclosed by leaves.

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

Leaves spiral; not scale-like; compound; pinnate, or with two leaflets; without a terminal leaflet; leaflets opposite, or leaflets alternate; all of the same type; not modified into spines; coriaceous, or paper-like; not gland-dotted; symmetric at the base; not dissected; smooth margined. Epidermis not waxy. Venation pinnate. Secondary veins open; not prominent, but visible. Smallest veins not prominent, but visible; net like. Intramarginal vein present. Stalk of blade less than a quarter the length of the blade; not winged; attached to base of leaf blade; swollen; swollen at one end. Stipules present; joined; laterally placed; not encircling the twig; scale-like; not fringed; small; not persistent. Domatia absent. Basal glands absent. Hairs on mature leaf absent.

Inflorescences present; terminal, or axillary; 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; with one plane of symmetry; with male or female parts raised on a column; with the female parts of the flower raised on a stalk. Hypanthium present. Disk absent. Perianth present; with distinct calyx and corolla whorls. Sepals 4; partially joined; not persistent in fruit; not growing any further after flowering. Epicalyx absent. Petals present; 1; free; not fleshy; deciduous; stalked; entire. Stamens 3 (plus 4-7 staminodes); filaments present; joined (base); free of the perianth; all equal in size; anisomerous. Anthers 2 loculed; attached along the side; not awned; dehiscing by long slits. Ovary superior. Carpels solitary; 1. Locules 1. Styles solitary. Stigmas 1 lobed; distinctive; head shaped. Fruit legume-like; non-fleshy; not multiple; splitting; not enclosed in, or sitting on, fleshy perianth parts; wingless. Seeds 3-10 per fruit; about 1 cm long to much more than 1 cm long; wingless; uniform in cross-section; aril absent; non-endospermic.

Large buttressed trees; leaflets opposite and no terminal leaflet; 3 (rarely four) stamens obvious; one petal only; fruit woody, opening to reveal a few large, oval and flat, seeds.


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.