Echinocereus arizonicus subsp. nigrihorridispinus Echinocereus arizonicus subsp. nigrihorridispinus W.Blum & Rutow, Echinocereus Monogr.: 3. 1998 sec. Baker 200611. Baker, M. A. 2006: Circumscription of Echinocereus arizonicus subsp. arizonicus: Phenetic analysis of morphological characters in section Triglochidiatus (Cactaceae), part II. – Madroño 4: 388-99Content