Description from Flora of China
Trees. Leaves abruptly pinnate, with few pairs of leaflets, leathery; stipules 2, usually united to a conical sheath, caducous; petiole robust, with glandular nodes. Corymbose panicles axillary or terminal; involucre caducous; bract 1, deciduous or persistent, smaller or larger than bracteoles, hairy or glabrous; bracteoles 2, usually persistent, subopposite, colored. Flowers bisexual or unisexual, yellowish to deep red, with short pedicels. Calyx tubular; tube elongated, slightly inflated in upper part, with a disk at apex; lobes 4, rarely 5 or 6, petaloid, ovate-oblong, slightly unequal in size, imbricate. Petals absent. Stamens 4-10, all perfect or 1 or 2 reduced, inserted in disk on throat of calyx tube; filaments free, elongated, often reflexed in bud; anthers oblong or suborbicular, dorsifixed, cells opening lengthwise. Ovary compressed, oblong, hairy or glabrous, shortly stalked, stalk adnate to calyx tube; ovules few to more than 10; style filiform; stigma terminal, capitate. Legume compressed, oblong, slightly curved and oblique, leathery to rather woody, 2-valved. Seeds 1-8, compressed, elliptic to ovoid; testa thin, crustaceous; radicle small, straight.
About 20 species: tropical Asia; two species in China.
(Authors: Chen Dezhao (陈德昭 Chen Te-chao), Zhang Dianxiang (张奠湘); Ding Hou)