Description from Flora of China
Gymnanthemum extensum (Candolle) Steetz; Vernonia subarborea Vaniot.
Shrubs or subshrubs, 2-3 m tall. Branches terete, striate, densely yellowish brown puberulent and glandular. Petiole 5-10 mm, densely puberulent; leaf blade oblong or oblong-lanceolate, 9-12 × 3-7.5 cm, thick or submembranous, abaxially densely or sparsely yellow puberulent, glandular, adaxially dark green, adpressed hispidulous or ± glabrescent, lateral veins 9- or 10-paired, veins abaxially ± raised, veinlets inconspicuously reticulate, base cuneately attenuate, margin mucronate-serrate, apex acuminate. Synflorescences usually terminal and subterminal, panicles lax or dense, flat-topped. Capitula many, 4-5 mm in diam.; peduncles (3-)5-8 mm; bracteoles 1 or 2, linear, densely yellowish puberulent and glandular. Involucre cylindric, 6-7 × 4-5 mm; phyllaries few, ca. 5-seriate, yellow-green or with reddish purple tip, leathery, concave, ovate-oblong, puberulent or subglabrous, apex obtuse, outermost very short, inner linear-oblong, 6-7 × 1-1.5 mm. Receptacle small and flat, foveolate. Florets 8-10; corolla white or reddish, tubular, 8-10 mm, glandular-puberulent; lobes linear-lanceolate, 2.5-3 mm, apically glandular. Achenes oblong-cylindric, ca. 4 mm, 10-ribbed, puberulent and glandular. Pappus 2-seriate, reddish; outer setae few, short; inner setae 8-10 mm, scabrid. Fl. Oct-Mar.
This taxon was first named "Conyza extensa" (in Wallich, Numer. List, no. 3016. 1831), which is a nomen nudum and was therefore not validly published. Material of this species has been misidentified as Vernonia cylindriceps C. B. Clarke (see Merrill, Brittonia 4: 182. 1941).
Open forests or thickets in valleys, roadsides on slopes; 1200-2100 m. Guizhou, Yunnan [Bhutan, India (Sikkim), Myanmar, Nepal].