Opuntia the Americas. Through human actions, they have since been introduced to many other areas of the world. Prickly pear species are found in abundance in Mexico, especially in the central and western regions, and in the Caribbean islands (West Indies). In the United States, prickly pears are native to many areas of the arid, semi-arid, and drought-prone Western and South Central United States, including the lower elevations of the Rocky Mountains and southern Great Plains, where species such as "Opuntia phaeacantha" and "Opuntia polyacantha" become dominant, and to the desert Southwest, where several types are endemic. Prickly pear cactus is
Opuntia basilaris These are more or less blue-gray, depending on variety, long and less than wide and thick. They are typically spineless, but have instead many small barbed bristles, called glochids, that easily penetrate the skin. "Opuntia basilaris" blooms from spring to early summer. The species is variable in nature and several names under different ranks have been described. Only four of these are generally accepted. Some experts consider the Trelease's beavertail to be a full species (Bowen 1987, R. van de Hoek). It is unique among the varieties of "Opuntia basilaris" in that the areoles contain spines in addition to the