Opuntia Basilaris

Opuntia basilaris, the Beavertail Cactus, is a cactus species found in southwest United States. It occurs mostly in the Mojave Desert, Anza-Borrego Desert State Park, and Colorado Deserts, and also in the Colorado Plateau and northwest Mexico; it ranges through the Grand Canyon and Colorado River region to southern Utah, and in western Arizona, regions along the Lower Colorado River Valley. The Beavertail Cactus is a medium-sized to small prickly pear cactus, depending on variety, growing to about 60 cm tall. A single plant may consist of hundreds of fleshy, flattened pads. These are more or less blue-gray, depending on variety, growing to a length of 14 cm and are maximum 10 cm wide and 1 to 1.5 cm thick. They are typically spineless, but have instead many small barbed bristles, called glochids, that easily penetrate the skin. The pink to rose colored flowers are most common; however, a rare variety of white and even yellow flowers also exist. Opuntia basilaris bloom from spring to early summer.

There are two subspecies and several varieties of this species:

• Opuntia basilaris subsp. basilaris
  • Opuntia basilaris var. albiflorus
  • Opuntia basilaris var. aurea
  • Opuntia basilaris var. brachyclada
  • Opuntia basilaris var. cordata
  • Opuntia basilaris var. heilii
  • Opuntia basilaris var. humistrata
  • Opuntia basilaris var. longiareolata - Elongated Beavertail Prickly Pear
  • Opuntia basilaris var. ramosa
  • Opuntia basilaris var. treleasei - Trelease's Beavertail Prickly Pear, Bakersfield Cactus (This Species is designated as endangered under the federal Endangered Species Act and California Endangered Species Act, which means that killing or possessing it is prohibited in California)
  • Opuntia basilaris var. woodburyi
• Opuntia basilaris subsp. whitneyana
  • Opuntia basilaris subsp. whitneyana var. whitneyana

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 eye-spots contain spines in addition to the bristles; this indicates that the species does vary a lot in its exterior.