Castilleja exserta (A. Heller) T.I. Chuang & Heckard subsp. exserta Castilleja exserta (A. Heller) T.I. Chuang & Heckard subsp. exserta in Syst. Bot. 16(4): 657. 1991 sec. Méndez-Larios & Villaseñor 2001