Arpophyllum medium Rchb. f. Arpophyllum medium Rchb. f. in Beitr. Orchid.-K. C. Amer.: 89-90. 1866 sec. Soto-Arenas & al. 2007=Arpophyllum giganteum subsp. medium (Rchb. f.) Dressler in Novon 10(3): 193. 2000 syn. sec. Hágsater & Soto-Arenas 2003