About Echinocereus viereckii Werderm.
Echinocereus viereckii Werderm. grows either upright or prostrate, and branches from its base. Its dull, shiny light green shoots typically grow up to 20 cm (7.9 in) long and 4 to 4.5 cm (1.6 to 1.8 in) in diameter. The shoot apex is loosely covered in white-yellowish areole felt, and is topped by an upright hyaline-yellow spine. This cactus has 8 to 9 straight, sharply separated ribs at the apex that run vertically down the shoot, reaching about 6 to 8 mm (0.24 to 0.31 in) in height. The ribs are deeply indented between the areoles, forming mammillary-like humps. It has 7 to 9 radial spines that spread horizontally, are evenly spaced, and are usually 5 to 7 mm (0.20 to 0.28 in) long. It also has 4 central spines that are thickened at the base and can grow up to 2 cm (0.79 in) long. Its funnel-shaped flowers can reach up to 11 cm (4.3 in) in diameter, are purplish-pink, and have a glassy flower tube with light golden brown thorns. Echinocereus viereckii is native to the Mexican states of Nuevo León and Tamaulipas.
