Arnica amplexicaulis var. piperi H. St.John & Warren
Arnica amplexicaulis var. piperi H. St.John & Warren is a synonym sensu FNA Ed. Comm., 2006c of:
Arnica lanceolata subsp. prima (Maguire) Strother & S.J. Wolf, an accepted subspecies name sensu FNA Ed. Comm., 2006c.