One variety of this species, Echinocereus fendleri var. kuenzleri, Kuenzler's hedgehog cactus' (formerly Echinocereus kuenzleri), is rare and federally listed as an endangered species of the United States. When it was listed in 1979, there were only 200 known individuals of this variety remaining, all in the Sacramento Mountains of New Mexico. It was threatened with extinction by poachers, who removed many plants from the wild.