Description from Flora of China
Herbs, annual, biennial, monocarpic perennial, perennial, or shrubby. Laticifers or elongated idioblasts present. Leaves alternate or in a basal rosette, rarely opposite or whorled, usually without stipules; leaf blade entire to compound. Inflorescences racemes, panicles, dichasia, pseudoumbels, or solitary flowers. Flowers actinomorphic, bisymmetric, or zygomorphic, always bisexual, usually 2-merous, rarely 3- or 4-merous. Calyx caducous, green or petaloid. Corolla choripetalous or quasi-sympetalous, very rarely absent. Anthers opening by slits. Ovary superior, syncarpous with 2 to several carpels; placentation parietal.
Many species are used medicinally due to the high content of alkaloids.
The two subfamilies recognized here are often treated as separate families.
Wu Chengyi, Chuang Hsuan & Su Ziyun. 1999. Papaveraceae. In: Wu Chengyi, ed., Fl. Reipubl. Popularis Sin. 32: 1-483, 541-545.
Forty genera and ca. 800 species: mainly in the N Hemisphere of both the Old and New Worlds, extending into Central and South America, a few in Africa; 19 genera (one endemic, two introduced) and 443 species (295 endemic, five introduced, one requiring verification) in China.
(Authors: Zhang Mingli (张明理), Su Zhiyun (苏志云 Shu Tsi-yun); Magnus Lidén, Christopher Grey-Wilson)