Arnica unalaschcensis

Plants 8-30 cm. Stems simple (sparsely to moderately hairy, hairs translucent with purple septa). Leaves 2-5 pairs, mostly cauline; petiolate (proximal) or sessile; blades elliptic-oblanceolate, obovate or spatulate, (3-)5-12 × 1.5-3 cm, margins usually entire proximal to mid blade, serrate to dentate distally, apices acute to obtuse or abruptly pointed, faces usually glabrate, sometimes scabrous to sparsely stipitate-glandular. Heads 1 (erect). Involucres hemispheric or turbinate-hemispheric (bases moderately villous). Phyllaries 14-24, lanceolate (apices obtuse, tips blunt, callous). Ray florets 6-17; corollas yellow (laminae 12-17 mm). Disc florets: corollas yellow; anthers dark purple. Cypselae brown, 4-5 mm, shortly hispidulous (hairs duplex, apically forked) and stipitate-glandular; pappi tawny, bristles subplumose. 2n = 38.

Flowering Jun-Aug. Coastal tundra to alpine slopes; 0-1500 m; Alaska; Asia (Japan, Russian Far East).