Arnica angustifolia subsp. attenuata (Greene) G.W. Douglas & Ruyle-Douglas
Arnica angustifolia subsp. attenuata (Greene) G.W. Douglas & Ruyle-Douglas is a synonym sensu Downie & Denford, 1988 of:
Arnica angustifolia Vahl subsp. angustifolia, an accepted subspecies name sensu FNA Ed. Comm., 2006c.