Echinomastus erectocentrus var. erectocentrus  Needlespine Cactus
CACTUS.  A small cylindrical or egg-shaped cactus with long thin white and purple spines.  Central spines 1 or 2, erect, dark purple, longer than the radial spines.  Flowers white, washed with pale pink or purple, with green centers.  Stigma pinkish red, style yellow, stamens yellow.  Blooms in March-April.  Appears to be endemic to the Empire Mountains and surrounding area. Its natural range is quite small, and the Empires hold the largest and healthiest populations.  Here it is common on flat ground or gentle slopes in limestone, marble, or mixed carbonate/volcanic gravel.  Associated plants may include Calliandra eriophylla, Tiquilia canescens, Larrea tridentata, Parthenium incanum.  Escobaria vivipara is similar but radial spines are white, central spines are brown and horizontal, and flowers are bright pink and bloom later.  See my E. erectocentrus page for more photos and information.
FAMILY:  Cactaceae (Cactus Family)