对节刺属 dui jie ci shu

Herbs annual, glabrous or hispidulous; branches dichotomous or opposite. Leaves opposite or alternate, acicular or terete, stiff, base expanded. Flowers solitary or clustered in glomerules in leaf axils, bisexual or unisexual. Perianth 4- or 5-parted; segments broadly ovate to oblong, membranous or leathery, abaxially usually transversely winged in fruit, apex obtuse, acute, or awned. Disk cupular; lobes semiorbicular. Stamens 5, inserted between lobes of disk; filaments subulate; anthers cylindric to broadly elliptic, with or without an awnlike appendage. Ovary base sunken in disk; ovule sessile; style very short; stigma capitulate, 2- or 3-lobed. Utricle abaxially convex, adaxially slightly concave; pericarp membranous, more fleshy basally, free from seed. Seed horizontal or oblique, depressed globose; testa membranous; embryo spiral, slender; perisperm absent.

About seven species: from the Caspian region to NW China (Xinjiang); one species in China.

Lower Taxon

• Horaninovia ulicina Fischer & C. A. Meyer