Rayless Arnica, Rayless Leopardbane: Arnica discoidea (Synonyms: Arnica discoidea var. eradiata, Arnica grayi, Arnica parviflora, Arnica parviflora ssp. alata, Arnica parviflora ssp. parviflora)
Nodding Arnica, Parry's Arnica: Arnica parryi (Synonyms: Arnica angustifolia, Arnica angustifolia ssp. eradiata, Arnica parryi ssp. parryi, Arnica parryi ssp. sonnei, Arnica parryi var. parryi, Arnica parryi var. sonnei) -