《中国植物志》|| 罂粟科 PAPAVERACEAE ||实心延胡索组 Sect. Pes-gallinaceus Irmisch ||延胡索 Corydalis yanhusuo W. T. Wang ex Z. Y. Su & C. Y. Wu

285.延胡索（开宝本草）元胡（中药志）图版116：1-5 Corydalis yanhusuo W. T. Wang ex Z. Y. Su et C. Y. Wu in Act. Bot. Yunnan. 7 (3): 260. 1985; Y. H. Zhang,现代应用药学 6 (2): 14. 1989; Y. H. Zhang et al. in ibid., 7 (5): 1. 1990; et ibid., 12 (1) 36, in tabl. 1990;湖北植物大全: 69. 1993. ——C. yanhusuo W. T. Wang, 中国高等植物图鉴2: 12, 图1754. 1972, nom. seminud. et补编1: 662, in clavi sin. 1982; Liou Min-yuan et al. in Bull. Bot. Lab. North-East. For. Inst. 4: 31-37, f. 2. 1979, nom. seminud.; 湖北植物志2: 13, 图695. 1979; nom. seminud. ——C. ambigua auct. non. Cham. et Schlecht: E. P. Smith Mater. Medic. et Nat. Hist. China 75. 1971; 南京药学院, 药材学409、1959; 浙江中药手册1: 47. 1959; B. Laufer, Sino-Iranica 197. 1967.——C. bulbosa auct. non (L.) DC: Forbes et Hemsl. in Journ. Linn. Soc. Bot. 23: 36. 1886 p. p.; Pei in Contr. Biol. Lab. Sci. Soc. China Ser. 8: 297. 1933; 杨时泰, 本草述銘元141. 1958; 江苏南部种子植物手册306, f. 488. 1959;中药志1 ed., 1: 263. 1959; 杭州药用植物志121, f. 65. 1961; 中华人民共和国药典109. 1963; 浙江民间常用草药3: 97, 图36-1. 1972. ——C. turtschaninowii f. yanhusuo Y. H. Chou et C. C. Hsu in Acta Phytotax. Sin. 15: 82, f. 1-2. 1977;中药志2 ed. 1: 60, color fig. 26. 1979.
多年生草本，高10-30厘米。块茎圆球形，直径(0.5-)1-2.5厘米，质黄。茎直立，常分枝，基部以上具1鳞片，有时具2鳞片，通常具3-4枚茎生叶，鳞片和下部茎生叶常具腋生块茎。叶二回三出或近三回三出，小叶三裂或三深裂，具全缘的披针形裂片，裂片长2-2.5厘米，宽5-8毫米；下部茎生叶常具长柄；叶柄基部具鞘。总状花序疏生5-15花。苞片披针形或狭卵圆形，全缘，有时下部的稍分裂，长约8毫米。花梗花期长约1厘米，果期长约2厘米。花紫红色。萼片小，早落。外花瓣宽展，具齿，顶端微凹，具短尖。上花瓣长(1.5-)2-2.2厘米，瓣片与距常上弯；距圆筒形，长1.1-1.3厘米；蜜腺体约贯穿距长的1/2，末端钝。下花瓣具短爪，向前渐增大成宽展的瓣片。内花瓣长8-9毫米，爪长于瓣片。柱头近圆形，具较长的8乳突。蒴果线形，长2-2.8厘米，具1列种子。
产安徽、江苏、浙江、湖北、河南（唐河、信阳），生丘陵草地，有的地区有引种栽培（陕、甘、川、滇和北京）。选模式标本采自浙江的杭州。
块茎为著名的常用中药，含20多种生物碱，用于行气止痛、活血散瘀、跌打损伤等。延胡索又名“茅山玄胡索”，始见于清代李中立的《本草原始》，据载，自明代以来，延胡索产地南下，“茅山延胡索”和“西延胡索”并称于世。“茅山玄胡索皮青黄，肉黄，形小而坚，此品最佳，“今之茅山上龙洞，仁和（今杭州）笕桥亦种之”。“西玄胡索大而皮黑，肉黄，此样力微”，显然它是产于新疆的薯根延胡索和长距延胡索及其邻近种。宋唐以前的延胡索产于东北和华北（见齿瓣延胡索条），产地南下而为“茅山玄胡素”所取代，西迁而为“西玄胡索”所更替，实由于南宋南迁，北方商道堵塞后所自然形成的。今人但知今之延胡素产于南方，而不知古之延胡索产于北方，而将它视为代用品了。

《Flora of China》|| Papaveraceae || Corydalis ||延胡索 Corydalis yanhusuo

60. Corydalis yanhusuo (Y. H. Chou & C. C. Hsu) W. T. Wang ex Z. Y. Su & C. Y. Wu, Acta Bot. Yunnan. 7: 269. 1985.

延胡索 yan hu suo

Corydalis turtschaninovii Besser f. yanhusuo Y. H. Chou & C. C. Hsu, Acta Phytotax. Sin. 15(2): 82. 1977; C. ternata (Nakai) Nakai f. yanhusuo (Y. H. Chou & C. C. Hsu) Y. C. Zhu.

Herbs, perennial. Tuber yellow, rounded, (0.5-)1-2.5 cm in diam. Stems erect, 10-30 cm, with 1 or sometimes 2 scale leaves, with 2 or often 3(or 4?) cauline leaves, scales and lower cauline leaves often with axillary tuber. Leaves biternate or nearly triternate; leaflets 2-2.5 cm × 5-8 mm, entire to deeply trifid with lanceolate entire acute segments; lowermost cauline leaf often long petiolate and vaginate at base. Raceme lax, 5-15-flowered; bracts lanceolate or narrowly ovate, 5-12 × 2-5 mm, margin entire, apex acute, sometimes lower bracts slightly divided. Pedicel ca. 10 mm at flowering, in fruit to 20 mm. Flowers amaranth. Sepals caducous, small. Outer petals with broad dentate limbs, emarginate with a mucro in notch; spur of upper petal upcurved, cylindric, 11-13 mm; nectary extended through ca. 1/2 of spur, apex obtuse; lower petal with short claw; inner petals 8-9 mm, claw longer than petal lobes. Stigma nearly orbicular, papillae longer than in preceding species. Capsule linear, 20-28 mm. Seeds in 1 row. Fl. and fr. Apr-Jun.

● Grasslands on highlands. Anhui, Henan (Tanghe, Xinyang), Hubei, Hunan, Jiangsu, Zhejiang; cultivated in Beijing, Gansu, Shaanxi, Sichuan, and Yunnan.

This species is an important herb in traditional Chinese medicine.