1. Ixeridium gracile (Candolle) Pak & Kawano, Mem. Fac. Sci. Kyoto Univ., Ser. Biol. 15: 45. 1992.
细叶小苦荬 xi ye xiao ku mai
Lactuca gracilis Candolle, Prodr. 7: 140. 1838; Ixeris gracilis (Candolle) Stebbins.
Herbs 10-50 cm tall, perennial. Stem erect to ascending erect, weakly to moderately branched from basal third or higher up, glabrous, distantly leafy. Basal leaves narrowly spatulate, narrowly elliptic, or almost linear, 4-15 × 0.4-1 cm, basally attenuate, margin entire, apex acute. Stem leaves narrowly lanceolate to linear-lanceolate, base semiamplexicaul but never clasping. Synflorescence corymbiform to paniculiform-corymbiform, with some to many capitula. Capitula with 8-11 florets; peduncle capillaceous. Involucre narrowly cylindric, 7-8 mm. Phyllaries abaxially glabrous; outer phyllaries 4-6, ovate, less than ca. 1 mm, apex acute; inner phyllaries 7 or 8. Florets yellow. Anther tube and style greenish to blackish upon drying. Achene brown, subfusiform, 4.5-5.5 mm, apex attenuate into a slender 1-1.5 mm beak. Pappus pale yellow, ca. 3 mm. Fl. and fr. May-Jul.
Forests, forest margins; 1400-?2700 m. Xizang, Yunnan [Bhutan, NE India, Nepal].
Starting with J. D. Hooker (Fl. Brit. India 3: 410-411. 1881; see also FRPS 80(1): 257. 1997) and X. Zhuang (Fl. Yunnan. 13: 723. 2004), Ixeridium gracile has long been confused with the widespread I. beauverdianum (= I. makinoanum), see below, which has smaller involucres with only 5 inner phyllaries. Actually, I. gracile has a very restricted distribution and is a rather rare species. However, it is quite similar to I. laevigatum, and the delimitation between the two species should be reassessed.