Opuntia atrispina at the tips but dark brown at the bases. Opuntia atrispina Opuntia atrispina is a cactus species in the "Opuntia" genus. It has limited distribution in the United States. In Texas it can be found from near Uvalde to Del Rio/Langtry—a small strip of area just 50 miles long. The flowers on these small shrubs are special because they open pale yellow (sometimes almost white) and darken with age to rose. Thus, the plants can be adorned with flowers of multiple colors: cream, yellow, salmon, and rose. Newly opened flowers can even have a hint of green in the middle.
Opuntia arenaria strongly deflexed and much shorter. Overall, plants (clumps) of cladodes may be 20–30 cm across and about 4–8 cm tall. Fruits are small, about 2.5 cm. Opuntia arenaria Opuntia arenaria was considered a variety of "O. polyacantha" by many botanists, and is still treated that way in the Flora of North America. However, "O. arenaria" is diploid and "O. polyacantha" is tetraploid. It was described by Engelmann in 1856. "Opuntia arenaria" can grow in soil that is essentially pure sand. It has rhizomes up to 1.5 m long that give rise to above ground shoots with small cladodes that are