Arnica rydbergii var. dubia A. Nelson ex Hayward nom. inval.
Arnica rydbergii var. dubia A. Nelson ex Hayward nom. inval. is a synonym sensu Downie & Denford, 1988 of:
Arnica lonchophylla Greene, an accepted species name sensu FNA Ed. Comm., 2006c.
Arnica rydbergii var. dubia A. Nelson ex Hayward nom. inval. is a synonym sensu Downie & Denford, 1988 of:
Arnica lonchophylla Greene, an accepted species name sensu FNA Ed. Comm., 2006c.