trees, boles straight, crown dome-shaped or flat. Leaves with prominent
parallel nerves on the undersurface, petiole swollen and articulated near
lamina base, stipules large, caducous, Flowers on short, few-flowered axillary
panicles. Sepals 5, unequal, connate in a tube to form the ovary wall. Petals
oblong, contorted. Stamens numerous, connective prolonged into a long point or
appendaged. Ovary ovoid to conical, stylopodium cylindrical to filiform. Tube
of fruiting calyx with 5 ribs or winged, two of which develop into large wings. Fruit a nut with greatly
enlarged sepals, two of which much longer than the others.