Aster mekongensis Onno, p.p.

Herbs, perennial, 14-45 cm tall, sometimes caespitose; rhizomes robust, sometimes with short stolons. Stems erect or ascending, simple, sparsely villous (crosswalls purple), distally minutely stipitate glandular. Leaves basal and cauline; cauline leaves gradually reduced, thin, abaxially sparsely villous to pilosulose, adaxially glabrate or sparsely pilosulose, margin entire or remotely serrate to serrulate, apex mucronate; basal leaves withered at anthesis, sometimes marcescent, long winged petiolate (petiole to 10 cm); blade oblong to spatulate, 2-10 × 1-3.5 cm, base attenuate, apex acute or acuminate; lower to middle cauline leaves sessile, obovate to lanceolate, 3-9 × 1-2.8 cm, base cuneate to rounded, subclasping, apex acute to obtuse; upper cauline leaves 1.5-3 × 0.8-1.2 cm, apex acute. Capitula terminal, solitary, 7-8 cm in diam. Involucres hemispheric, 1.5-2.5 cm in diam.; phyllaries 2-seriate, equal, lanceolate to narrowly lanceolate, 15-20 mm, abaxially sparsely villous, densely minutely purple stipitate glandular, leaflike, margin long ciliate, apex long acuminate, often purplish; outer phyllaries 2-5 mm wide, proximally lanate and distally so on midvein, sometimes lanate more distally; inner phyllaries 2-3 mm wide. Ray florets 50-70, purplish blue, tube sparsely strigillose, lamina 30-40 × 1-1.5 mm, glabrous, eglandular; disk florets yellow, 7-9 mm, limb funnelform, 4-6 mm, sparsely strigillose proximally, lobes spreading, narrowly triangular, 1.8-2.3 mm, minutely stipitate glandular, tip purple. Achenes obovoid, compressed, 4-4.5 mm, glabrous or distally glabrate, moderately to densely minutely stipitate glandular, not winged, 2-ribbed. Pappus 3- or 4-seriate, reddish brown, bristles barbellate throughout; outermost bristles very few or none, slender, ca. 0.7 mm; outer bristles few, slender, 2-4 mm; inner bristles 5-5.5 mm, acute; innermost bristles ca. 6 mm, weakly clavate. Fl. Jul-Aug, fr. Aug-Nov.

● Alpine and subalpine meadows and screes, ledges of cliffs; 3300-4600 m. E Xizang, NW Yunnan.