6. ELLIPANTHUS J. D. Hooker in Bentham & J. D. Hooker, Gen. Pl. 1: 431, 434. 1862.
单叶豆属 dan ye dou shu
Shrubs or small trees. Leaves 1-foliolate; petiole articulate; leaf blade entire at margin. Inflorescences axillary, paniculate to glomerulate-racemose, small; bracts lanceolate, small, soon falling. Flowers bisexual (when protandrous) or unisexual (when plants dioecious), 4-or 5-merous. Sepals 4 or 5, valvate in bud, densely hairy abaxially, persistent but not enlarged after anthesis. Petals 4 or 5, free, imbricate in bud, longer than sepals. Stamens 2 × as many as petals, those opposite sepals well developed, those opposite petals much smaller and staminodal; filaments connate at base into a tube. Carpel 1, somewhat laterally inserted; ovary obliquely ovoid, flattened, hairy; ovules 2, erect, collateral. Style slender, hairy; stigma disk-shaped to 2-lobed, large. Follicle yellowish to brownish when mature, ovoid, tomentose abaxially, slightly to strongly abaxially geniculate, basal part narrowed into a short to long stipe, fertile part dehiscing by a longitudinal slit, with persistent calyx; pericarp woody. Seed 1, ellipsoid, obtuse at both ends; testa mostly black and glossy, basal part covered with a yellowish to orange, thin aril; endosperm ca. 1 mm thick, hard.
Between seven and 13 species: mainly in SE Asia, also in tropical E Africa and Madagascar; one species (endemic) in China.