Description from
Flora of China
Pistolochia Bernhardi.
Herbs, annual, biennial, or perennial, soft, juicy, usually glabrous. Leaves usually alternate, pinnately or ternately divided. Inflorescence a simple bracteate raceme (compound with cymose or racemose partial inflorescences in some species of Corydalis sect. Strictae). Flowers blue, purple, orange, yellow, or white. Sepals petaloid, usually dentate. Corolla zygomorphic; upper petal spurred. Stamens 2 (i.e., filaments of each triplet completely fused); median upper stamen with a nectariferous appendage at base frequently fused to spur for a shorter or longer portion. Stigma variable. Fruit a usually many-seeded capsule with persistent style. Seeds black, with whitish elaiosomes (except in C. sect. Bipapillatae).
Three subgenera and ca. 465 species: mainly N temperate (but one species in subarctic Russia/North America, one species in the mountains of E Africa, and three species in subtropical Indochina); three subgenera and 357 species (262 endemic, one requiring verification) in China.
(Authors: Zhang Mingli (张明理), Su Zhiyun (苏志云 Shu Tsi-yun); Magnus Lidén)