About Echinocereus poselgeri Lem.
Echinocereus poselgeri Lem. most often grows with multiple spreading shoots, and forms a tuberous rhizome that resembles a dahlia root. Its dark blue-green shoots are slender, cylindrical, and taper to a point. They reach lengths between 60 and 120 cm (24 to 47 inches), and have a diameter between 1 and 2 cm (0.39 to 0.79 inches). The shoots have eight to ten low, unnoticeable, non-tuberculated ribs. One dark, slightly flattened central spine, pointing toward the tip of the shoot, grows up to 9 mm (0.35 inches) long. The eight to 16 marginal spines are whitish or grayish with darker tips, and measure 2 to 4.5 mm (0.079 to 0.177 inches) long. The funnel-shaped flowers are a pale pinkish-magenta, and grow close to the tips of the shoots. They can grow up to 6 cm (2.4 inches) long and 7 cm (2.8 inches) across. The fruits are dark green to brown, egg-shaped, and covered in persistent wool and thorns. Echinocereus poselgeri grows in scrub valleys and hills in southern Texas, USA, and the Mexican states of Coahuila, Nuevo León, Tamaulipas, and San Luis Potosí. It is most often found at low elevations in sandy soil, growing at heights up to 1150 meters.