Echinomastus Warnockii

Echinomastus warnockii may be distinguished from some similar-looking species in the same region - far west Texas centered on the Big Bend area - by the spines; both the zero to four (usually one) central spines and 11 to 17 radial spines are similar in size and color. Other species have smaller, thinner radials. Spine clusters overlap, but do not hide the greyish green stem. Spine clusters form on tubercles which are arranged in spiral, vertical rows (13 of them). Spines are grey or pale yellow-brown, and up to one inch in length, the covering is relatively sparse, allowing the green stem color to be clearly visible. Plants are always solitary.

Relatively large flowers, one inch across, grow in springtime at the tip of the stem; they have a lobed green or yellow-green stigma at the center, surrounded by many stamens, with slender yellow filaments and darker yellow anthers, and tepals which are mostly white or pale cream, often with darker midstripes on the undersurface. The irregularly-shaped fruits are light green, maturing to purplish, and they appear between May and July.

Echinomastus warnockii is similar to echinomastus mariposensis, and is found in the same area, though prefers different substrates - the latter is restricted to limestone, the former all other soil types.