薯莨 (原变种) shu liang (yuan bian zhong)

Dioscorea angusta R. Knuth; ? D. formosana R. Knuth; D. matsudae Hayata; D. rhipogonoides Oliver (1889), not Hayata (1906).

Tubers usually globose, ovoid, gourd-shaped, or oblong, to 20 cm in diam.; transverse section red, drying purplish black. Leaf blade ovate to elliptic-lanceolate or narrowly lanceolate, 5--20 × (1--)2--14 cm.

Mixed forests, broad-leaved forests, scrub forests, mountain slopes, along rivers, roadsides; 300--1500 m. Fujian, Guangdong, Guangxi, Guizhou, Hainan, Hunan, S Jiangxi, S and W Sichuan, Taiwan, SE Xizang (Mêdog Xian), Yunnan, S Zhejiang [Thailand, Vietnam].

Material from Taiwan is somewhat distinct in that most collections tend to dry greenish and the leaf blade has less prominent tertiary venation. They have been regarded as a distinct species, Dioscorea matsudae, but there is no clear-cut distinction between this and typical D. cirrhosa var. cirrhosa, and so the former has been treated as a synonym of the latter. The affinities of D. formosana are not clear. The type collections (B, destroyed) were originally identified as a variety of D. rhipogonoides (var. aculeata Uline, nom. nud.), which is a synonym of D. cirrhosa var. cirrhosa. Prain and Burkill examined this material and noted that it was too poor to name though probably not D. cirrhosa. The protologue described a prominently prickly stem, a feature relatively unusual in D. sect. Enantiophyllum, so it is possible that at least part of the material might have belonged elsewhere.