Cynanchum auriculatum

Cynanchum auriculatum is a species of climbing vine swallowworts. Its Chinese name is niu pi xiao (leather eater). C auriculatum flowers between June and August; fruiting from August all the way to December. Cynanchum auriculatum is native to Asian temperate and tropical regions; found in China (in Sichuan, Xizang, and Yunnan provinces), Bhutan, Nepal, and the northern parts of Pakistan and India (it is also native to Kashmir). Its habitat is mountainous shrubland terrain, at elevations from 2800–3600 meters. Ethanol extracts derived from roots of C. auriculatum are being studied for use in anti-cancer medicine; one preliminary study found extracts to have some cytotoxic effects on certain human tumor cell lines. The tests were conducted, both in vitro and in vivo, on both human subjects, and mice.