17. Arum Linnaeus, Sp. Pl. 2: 964. 1753.
疆南星属 jiang nan xing shu
Authors: Heng Li & Peter C. Boyce
Herbs, tuberous. Cataphylls several. Leaves 2, simple; petiole sheathing; leaf blade hastate-sagittate or sagittate. Inflorescences 1(or 2), pedunculate; peduncle long or short. Spathe ultimately marcescent, convolute, base (tube) separated from limb by a constriction; spathe tube oblong or ovate; limb initially erect, cymbiform, concave or arched, later flopping forward or actively reflexing, ovate-lanceolate to oblong-lanceolate. Spadix sessile, shorter than to subequaling spathe; flowers unisexual, naked; female zone cylindric; ovary oblong, 1-loculed; ovules few on 2 or 3 parietal placentae; stigma sessile; sterile flowers (staminodes) usually present between female and male zones and also above male zone; appendix dark purple or yellow, cylindric-conic, cylindric, or clavate; male zone shorter; stamens 3 or 4, nearly tetragonal, short; connective convex; anthers obovoid, shorter than filaments, opening by an apical pore or longitudinal slit; sterile flowers broadly conic, filiform, ± thickened, verrucose, these between female and male zones recurved, those at distal part of male zone reflexed upward. Berries obovoid, few seeded. Seeds with endosperm; embryo axile.
Twenty-eight species: N Africa, SW Asia extending to C Asia, Europe; one species in China.