Description from Flora of China
Cynanchum sibiricum Willdenow, Ges. Naturf. Freunde Berlin Neue Schriften 124. 1799; Cyathella cathayensis (Tsiang & Zhang) C. Y. Wu & D. Z. Li; Cynanchum acutum var. longifolium (Martens) Ledebour; C. cathayense Tsiang & Zhang; C. longifolium Martens.
Roots ca. 2 cm in diam. Stems many branched and woody at base, twining to 3 m, villous to puberulent, sometimes glabrous. Petiole 0.5-4 cm; leaf blade hastate, hastate-cordate, or oblong-hastate, 1.3-6(-15) × 1.1-4.5(-8) cm, papery, base auriculate, apex acute to long acuminate, basal lobes recurved, parallel or divergent, ciliate, glabrous or densely pubescent along veins; basal veins 5-7, lateral veins ca. 3 pairs. Inflorescences racemelike; peduncle 0.5-5 cm, rachis to 7 cm. Pedicel 4-8 mm. Sepals ovate, 1.5-2 × 0.5-0.9 mm, puberulent outside, glandular inside. Corolla white outside, white to purple inside; tube ca. 1 mm; lobes narrowly ovate or oblong, ca. 4 × 1.3-2 mm, obtuse, glabrous. Corona cylindric, margin 5-lobed; lobes 3-fid with middle segment long threadlike, interior with 5 short appendages included within tube. Anthers nearly square, appendages ovate; pollinia oblong. Stigma head subapiculate. Follicles lanceolate to linear, 6.5-13 cm × 8-10 mm, puberulent. Seeds oblong-ovate, 5-7.5 × 2-2.5 mm; coma 2-3 cm. Fl. May-Aug, fr. Jun-Oct.
The plant is used medicinally to treat swellings.
Cynanchum acutum subsp. acutum is widespread in the Mediterranean region from Spain east to Iraq, where there is a small area of overlap with subsp. sibiricum. It differs by having
ovate leaves with convex sides.
Dry areas, waste places; 900-1400 m. Gansu, Hebei, Nei Mongol, Ningxia, Xinjiang, Xizang [Afghanistan, Kashmir, Kazakhstan, Mongolia, Pakistan, Russia, Turkmenistan; SW Asia]