Stephania is a genus of flowering plants in the family Menispermaceae, native to eastern and southern Asia and Australasia. They are herbaceous perennial vines growing to around four metres tall, with a large, woody caudex. The leaves are arranged spirally on the stem, and are peltate, with the leaf petiole attached near the centre of the leaf. The name Stephania comes from the Greek, "a crown". This refers to the anthers being arranged in a crown like manner.One species, S. tetrandra, is among the 50 fundamental herbs used in traditional Chinese medicine, where it is called han fang ji (漢防己, "Chinese fang ji"). Other plants named fang ji are sometimes substituted for it. Other varieties substituted include Cocculus thunbergii, C. trulobus, Aristolochia fanchi, Stephania tetrandria, and Sinomenium acutun. Notable among these is guan fang ji (廣防己, "Broad fang ji", Aristolochia fanchi. Because of its toxicity, it is used in TCM only with great caution.