线叶紫菀 xian ye zi wan

Shrubs, 60-100 cm tall. Stems multibranched, old branches ascending, bark brown, branched, shallowly striate, leaf scars and axillary buds prominent; current-year branches slender, yellow-brown, densely leafy, white tomentulose. Leaves sessile, adaxially green, linear, 1-4(-5) × 0.1-0.3(-0.5) cm, subleathery, abaxially gray-white tomentose, adaxially rugose, very sparsely scabrous, resinous, midvein pronounced, venation pinnate, base long cuneate, margin entire, strongly recurved, apex acute, mucronulate; upper leaves smaller. Capitula 3-50 or more in ± densely corymbiform synflorescences, terminal on current-year branches or 3-5 at ends of lateral branches, ca. 8 mm in diam.; peduncles slender, 2-6 mm, tomentulose; bracts subulate. Involucres narrowly campanulate, 5-6 mm; phyllaries 4- or 5-seriate, unequal; outer phyllaries ovate, 1-2 mm, sparsely tomentose, resinous, margin narrowly scarious, keeled, midvein apically swollen, translucent, apex acute; inner phyllaries lanceolate, 4-5 × 0.7-0.9 mm, margin narrowly scarious, erose, ciliate, midvein apically very swollen, apex obtuse to acute. Ray florets 5-7, white, tube sparsely hairy distally, lamina 2.5-3 × 0.5-0.8 mm, glabrous, eglandular; disk florets yellow, 3.5-4 mm, limb narrowly campanulate, ca. 3 mm, very sparsely hairy proximally, lobes spreading, narrowly triangular, 1.2-1.5 mm. Achenes cylindric, ca. 2.5 mm, moderately strigose, yellowish 6-8-ribbed. Pappus 3-seriate, straw-colored, of sparsely barbellulate bristles; outer bristles 0.5-0.7 mm; inner bristles 2-3 mm, acute; innermost bristles ca. 4 mm, clavate. Fl. Jun, fr. Jun-Sep.

● Subalpine stony slopes or riverbanks; 2000-2900 m. SW and W Sichuan, Yunnan.

Aster lavandulifolius differs from other Aster species by its linear leaves and cylindric achenes.

Aster motuoensis Y. L. Chen (Bull. Bot. Res., Harbin 8(3): 12. 1988), described from SE Xizang (Mêdog) as being close to A. lavandulifolius, differs from the latter in its notably reticulately veined, oblong to oblong-lanceolate leaves, narrowly cylindric involucres, and 4-6 ray florets. Further study is required to ascertain its status.