尖裂假还阳参(原亚种) jian lie jia huan yang shen (yuan ya zhong)

Youngia sonchifolia Maximowicz, Mém. Acad. Imp. Sci. St.-Pétersbourg Divers Savans 9: 180. 1859; Crepidiastrum sonchifolium var. elegans (Franchet) Sennikov; Ixeridium elegans (Franchet) C. Shih; I. sonchifolium (Maximowicz) C. Shih; Ixeris denticulata (Houttuyn) Stebbins subsp. elegans (Franchet) Stebbins; I. denticulata subsp. sonchifolia (Maximowicz) Stebbins; I. serotina (Maximowicz) Kitagawa; I. sonchifolia (Maximowicz) Hance; I. sonchifolia var. serotina (Maximowicz) Kitagawa; Lactuca bungeana Nakai; L. denticulata (Houttuyn) Maximowicz var. sonchifolia (Maximowicz) Maximowicz; L. elegans Franchet; L. sonchifolia (Maximowicz) Debeaux (1876), not Willdenow (1803); Paraixeris serotina (Maximowicz) Tzvelev; P. sonchifolia (Maximowicz) Tzvelev; P. sonchifolia var. serotina (Maximowicz) Kitagawa; Y. serotina Maximowicz.

Basal leaves and often lower stem leaves oblanceolate, apex rounded. Middle stem leaves sessile, narrowly ovate, lanceolate, or rarely ± elliptic, 2.5-9 × 0.5-3 cm, base very conspicuously auriculately clasping, auricles ± rounded; blade including auricles pinnatifid, pinnatipartite, or subpinnatisect, with short triangular (1-5 mm) to long narrowly triangular or sublinear (to 1.5 cm) acute lateral lobes and a larger acute terminal lobe, margin entire or sharply dentate. Upper stem leaves similar to middle stem leaves but smaller, usually less incised, less dentate, or entire especially in upper part of blade, apex long acuminate. Involucre 4.5-6.5 mm. Inner phyllaries plane or more often weakly to strongly crested or corniculate below apex. Anther tube and style yellow upon drying. Achene reddish brown, 2-3.2 mm including a slender 0.4-1 mm beak. Pappus 2-3 mm. Fl. and fr. Apr-Sep. 2n = 10*.

Grasslands on mountain slopes, thickets, floodplains, rocky stream beds, cliffs, roadsides; below 100-1900 m. Anhui, Chongqing, Gansu, ?Guangxi, Guizhou, Hebei, Heilongjiang, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, Nei Mongol, Shaanxi, Shandong, Shanxi, Sichuan [Korea, Mongolia, E Russia].

Stebbins (J. Bot. 75: 43-51. 1937) distinguished Ixeris denticulata subsp. elegans from I. denticulata subsp. sonchifolia by the slightly smaller involucres, distinctly crested or corniculate inner phyllaries, and more finely dentate leaves. In the material studied, this delimitation does not appear to work. Although, for example, the inner phyllaries are strikingly corniculate in the type of Lactuca elegans, there is no discontinuity but a rather continuous variation toward plants with only slightly crested or even plane phyllaries. Similar observations regard the other features listed.