Perennial herbs; stems clumped at base, erect, densely silver-sericeous. Leaves obovate in outline, 1-3×0.5-2 cm, subcoriaceous, upper surfaces sparsely hairy, beneath densely silver-sericeous; pinnately cleft or parted, lobes 2 pairs, margins crenate or dentate, base cuneate-decurrent; upper and basal leaves smaller. Heads ca. 2 cm wide, solitary, long-pedunculate; involucre subglobose, 10-13 mm wide, 5 mm long; outer bracts 3-6×1-3 mm, inner bracts 4-6×2-3 mm; ray florets 1-seriate, limb 6×2.5 mm, apex obtuse, white, tube 2 mm long; disc florets green-yellowish, 2 mm long.

TAICHUNG: Chingshan to Malunchiao, Peng 12437, 16924; Techi, Leu 350, Kao 10755.

Endemic; on rocky slopes at 1,200 to 1,400 m, rare.

This species was treated by Kitamura (1940) as a synonym of Chrysanthemum morii, which was followed by Li (1978) in first edition of Flora of Taiwan. The two are similar in having white ray florets and long-pedunclulate heads terminting the branches. Dendranthema morii is a limestone plant restricted to eastern Taiwan, whereas D. horaimontanum is confined to a small area in the central part of the Central Mountain Range.