《中国植物志》|| 大戟科 EUPHORBIACEAE ||乳浆大戟组 Sect. 12. Esula ||甘遂 Euphorbia kansui Liou ex S. B. Ho

75.甘遂（神农本草经）图版39: 5-8
Euphorbia kansui T. N. Liou ex S. B. Ho in秦岭植物志1 (3): 162 et 450. 1981; 宁夏植物志1: 430.图420.1986; 河南植物志2: 490.图1407.1986.中国沙漠植物3: 341.1987; J. S. Ma ＆C. Y. Wu in Collect. Bot. 21: 119. 1992. ——E. kansui Liou, 中国高等植物图鉴2: 624.图2978.1972, nom. nud.
多年生草本。根圆柱状，长20-40厘米，末端呈念珠状膨大，直径可达6-9毫米。茎自基部多分枝或仅有1-2分枝，每个分枝顶端分枝或不分枝，高20-29厘米，直径3-5毫米。叶互生，线状披针形、线形或线状椭圆形，变化较大，长2-7厘米，宽4-5毫米，先端钝或具短尖头，基部渐狭，全缘；侧脉羽状，不明显或略可见；总苞叶3-6枚，倒卵状椭圆形，长1-2.5厘米，宽4-6毫米，先端钝或尖，基部渐狭；苞叶2枚，三角状卵形，长4-6毫米，宽4-5毫米，先端圆，基部近平截或略呈宽楔形。花序单生于二歧分枝顶端，基部具短柄；总苞杯状，高与直径均约3毫米；边缘4裂，裂片半圆形，边缘及内侧具白色柔毛；腺体4,新月形，两角不明显，暗黄色至浅褐色。雄花多数，明显伸出总苞外；雌花1枚，子房柄长3-6毫米；子房光滑无毛，花柱3，2/3以下合生；柱头2裂，不明显。蒴果三棱状球形，长与直径均3.5-4.5毫米；花柱宿存，易脱落，成熟时分裂为3个分果爿。种子长球状，长约2. 5毫米，直径约2毫米，灰褐色至浅褐色；种阜盾状，无柄。花期4-6月，果期6-8月。
产于河南、山西、陕西、甘肃和宁夏。生于荒坡、沙地、田边、低山坡、路旁等。模式标本采自陕西（周至）。
本种根为著名中药（甘遂、甘遂子），苦寒有毒，具除水、利尿功效；主治各种水肿 等；全株有毒，根毒性大，易致癌，宜慎用。

《Flora of China》|| Euphorbiaceae || Euphorbia ||甘遂 Euphorbia kansui

76. Euphorbia kansui T. N. Liou ex S. B. Ho, Fl. Tsinling. 1(3): 450. 1981.

甘遂 gan sui

Herbs, 20-30 cm tall. Rootstock irregularly swollen, somewhat moniliform, 20-40 cm × 6-9 mm thick. Stems many branched basally, sometimes only few, 3-5 mm thick. Leaves alternate; stipules absent; petiole absent; leaf blade linear-lanceolate, linear, or linear-elliptic, very variable, 2-7 cm × 4-5 mm, base attenuate, entire, apex obtuse or acuminate; lateral veins inconspicuous. Cyathophylls 3-6, obovate-elliptic, 1-2.5 cm × 4-6 mm, base attenuate, apex obtuse or acute. Cyathium subsessile; involucre cuplike, ca. 3 × 3 mm, lobes rounded, white pilose on margin and inside; glands 4, dark yellow to pale brown, crescent-shaped, 2 horns inconspicuous. Male flowers many, exserted from involucre. Female flower: ovary pedicel 3-6 mm, exserted from cup; ovary smooth, glabrous; styles connate below 2/3, persistent, easily fallen; style arms slightly 2-lobed. Capsule trigonous-globose, 3.5-4.5 × 3.5-4.5 mm. Seeds long globose, ca. 2.5 × 2 mm, gray-brown to light brown; caruncle present, peltate, sessile. Fl. Apr-Jun.

● Fields, roadsides, low mountain slopes. Gansu, Henan, Ningxia, Shaanxi, Shanxi.

The root is used in traditional Chinese medicine.