Dioon edule var. angustifolium (Miq.) Miq. Dioon edule var. angustifolium (Miq.) Miq. in Arch. Neerl. Sci. Exact. Nat. 3: 427. 1868 sec. Govaerts 2013=Dioon edule subsp. angustifolium (Miq.) A.E. Murray in Kalmia 13: 5. 1983 syn. sec. The Plant List 2013