Herbs, perennial, 40-50 cm tall, rarely caespitose, rhizomatous. Stems erect, simple, stout, flexuous, shallowly striate, glabrous proximally, sparsely strigillose distally, eglandular. Leaves: basal leaves in a rosette, disappearing before stem elongation, winged long (petiole to 2.5 cm) or shortly petiolate; blade abaxially pale green, adaxially green, oblong, 4-6 × 1.5-2.5 cm, slightly reduced upward, abaxially glabrous, veins sparsely strigillose, very sparsely minutely stipitate glandular in pits, adaxially densely scabridulous, very sparsely minutely stipitate glandular in pits, base abruptly attenuate, margin coarsely serrate (teeth mucronate), ciliate, midvein prominent, apex acuminate, mucronate; lowest leaves withered by anthesis (not seen); lower leaves (not seen) to upper leaves shortly broadly winged petiolate (base clasping) or sessile, lanceolate, 11.5-17 × 2.8-6 cm, base attenuate; synflorescence leaves sessile, lanceolate, ca. 3.3 × 1 cm, base auriculate, clasping, rapidly becoming bracts. Capitula numerous, in terminal corymbiform synflorescences, 1.5-1.8 cm in diam.; peduncles 10-20 mm, densely strigillose, minutely stipitate glandular; bracts linear-lanceolate, entire. Involucres campanulate, 5-6 × 6-7 mm; phyllaries 2- or 3-seriate, subequal, green, lanceolate to oblong-lanceolate, 4-6 × 1-1.2 mm, abaxially sparsely strigillose proximally on veins, moderately to sparsely minutely stipitate glandular proximally, margin scarious or narrowly scarious, erose, sparsely ciliate, midvein more pronounced basally, ± translucent, apex acuminate, sometimes purplish, eciliate. Ray florets 25-30, white, tube hairy, stipitate glandular, lamina 5-7 × 1-1.2 mm, (2-veined), glabrous, eglandular; disk florets yellow, ca. 5 mm, tube base flared, veins prominent, translucent, limb campanulate, ca. 3.2 mm, hairy, very sparsely stipitate glandular, lobes spreading, narrowly triangular, ca. 1.2 mm. Achenes (immature) obovoid, slightly compressed, ca. 3 mm, sparsely strigillose, sparsely minutely stipitate glandular apically, 2-ribbed. Pappus 3- or 4-seriate, dirty white or slightly reddish; outermost bristles slender, ca. 0.5 mm; outer bristles few or none, slender, ca. 3 mm; inner bristles ca. 4.2 mm, acute; innermost bristles 4.6-4.7 mm, clavate. Fl. unknown, fr. Nov.

The above description of Aster nigromontanus is based on the co-type at MO.

● Grasslands on slopes; 1500-3000 m. Yunnan (Jingdong, Mengzi).