Regularity: Regularly occurring
Global Range: California, Nevada, Utah, Arizona, Mexico.
Habitat and Ecology
Comments: Sandy soils, gravelly or rocky soils of plains, valleys, washes, or canyons in the desert, woodland, grassland,
Mojave Desert Habitat
This taxon is found in the Mojave Desert, the smallest of the four North American deserts. While the Mojave lies between the Great Basin Shrub Steppe and the Sonoran Desert, its fauna is more closely allied with the lower Colorado division of the Sonoran Desert. Dominant plants of the Mojave include Creosote Bush (Larrea tridentata), Many-fruit Saltbush (Atriplex polycarpa), Brittlebush (Encelia farinosa), Desert Holly (Atriplex hymenelytra), White Burrobush (Hymenoclea salsola), and Joshua Tree (Yucca brevifolia), the most notable endemic species in the region.
The Mojave’s warm temperate climate defines it as a distinct ecoregion. Mojave indicator species include Spiny Menodora (Menodora spinescens), Desert Senna (Cassia armata), Mojave Indigobush (Psorothamnus arborescens), and Shockley's Goldenhead (Acamptopappus shockleyi). The Mojave supports numerous species of cacti, including several endemics, such as Silver Cholla (Opuntia echinocarpa), Mojave Prickly Pear (O. erinacea), Beavertail Cactus (O. basilaris), and Cotton-top Cactus (Echinocactus polycephalus).
While the Mojave Desert is not so biologically distinct as the other desert ecoregions, distinctive endemic communities occur throughout. For example, the Kelso Dunes in the Mojave National Preserve harbor seven species of endemic insects, including the Kelso Dunes Jerusalem Cricket (Ammopelmatus kelsoensis) and the Kelso Dunes Shieldback Katydid (Eremopedes kelsoensis). The Mojave Fringe-toed Lizard (Uma Scoparia), while not endemic to the dunes, is rare elsewhere. Flowering plants also attract butterflies such as the Mojave Sooty-wing (Pholisora libya), and the widely distributed Painted Lady (Vanessa cardui).
There are a total of eight amphibian species present in the Mojave Desert all of which are anuran species: the endemic Relict Leopard Frog (Lithobates onca); the endemic Amargosa Toad (Anaxyrus nelsoni); Lowland Leopard Frog (Lithobates yavapaiensis); Red-spotted Toad (Anaxyrus punctatus); Southwestern Toad (Anaxyrus microscaphus); Great Basin Spadefoot (Spea intermontana); Great Plains Toad (Anaxyrus cognatus); and the Pacific Treefrog (Pseudacris regilla).
The native range of California’s threatened Desert Tortoise (Gopherus agassizii) includes the Mojave and Colorado Deserts. The Desert Tortoise has adapted for arid habitats by storing up to a liter of water in its urinary bladder. The following reptilian fauna are characteristic of the Mojave region in particular: Gila Monster (Heloderma suspectum NT); Western Banded Gecko (Coleonyx variegatus), Northern Desert Iguana (Dipsosaurus dorsalis), Western Chuckwalla (Sauromalus obesus), and regal horned lizard (Phrynosoma solare). Snake species include the Desert Rosy Boa (Charina trivirgata gracia), Mojave Patchnose Snake (Salvadora hexalepis mojavensis), and Mojave Rattlesnake (Crotalus scutulatus).
Endemic mammals of the ecoregion include the Mojave Ground Squirrel (Spermophilus mohavensis) and Amargosa Vole (Microtus californicus scirpensis); and the California Leaf-nosed Bat (Macrotus californicus).
Mojave Desert flora associations
Beavertail cactus, Opuntia basilaris, is found in California's Mojave Desert as one of the locations of occurrence of this species, . Some of the common flora associates are Shockley's goldenhead, Acamptopappus shockleyi; Desert senna, Cassia armata; Mojave dalea, Psorothamnus arborescens;and Spiny menodora, Menodora spinescens . Example cacti associates in this desert are: Mojave prickly pear, Opuntia erinaceatia; Silver cholla, O. echinocarpa, O. basilaris; and Many-headed barrel cactus, Echinocactus polycephalus. The chief megaflora of this desert region is the Joshua tree, Yucca brevifolia. Soils here in the Mojave are mainly coarse sands and gravels with many outcrops that offer diverse habitat niches
Number of Occurrences
Note: For many non-migratory species, occurrences are roughly equivalent to populations.
Estimated Number of Occurrences: 81 to >300
Comments: Over 100 EO's (Benson 1982).
IUCN Red List Assessment
Red List Category
Red List Criteria
National NatureServe Conservation Status
Rounded National Status Rank: N5 - Secure
NatureServe Conservation Status
Rounded Global Status Rank: G5 - Secure
Reasons: Widespread throughout the southwestern United States. EGR supports GRANK of G4G5 (86-05-08).
Comments: Most cacti subject to horticultural collecting.
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.
The species is variable in nature and several names under different ranks has been described to science. Only four of these are generally accepted.
- Opuntia basilaris var. basilaris
- Opuntia basilaris var. brachyclada - Little beavertail pricklypear
- Opuntia basilaris var. longiareolata - Elongated Beavertail Prickly Pear or Grand Canyon beavertail pricklypear
- Opuntia basilaris var. treleasei - Trelease's Beavertail Prickly Pear, Bakersfield Cactus (This variety 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)
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.
Beavertail Cactus with buds in Joshua Tree National Park
Flowering Beavertail Cactus in Joshua Tree National Park
Large flowering Beavertail Cactus in Joshua Tree National Park
Pink Beavertail Cactus flower in full bloom in Joshua Tree National Park
Insect covered pink Beavertail Cactus flower in full bloom in Joshua Tree National Park
Budding yellow Beavertail Cactus at Landers, California
|Wikimedia Commons has media related to Opuntia basilaris.|
- cite web|title=Plant Chemistry|http://findmeacure.com/2012/02/16/opuntia-basilaris/
- "Cahuilla Plants". enduringknowledgepublications.com. Retrieved 2012.
- "Temalpakh Ethnobotanical Garden". http://www.malkimuseum.org. Retrieved 2007.
Names and Taxonomy
Comments: Opuntia basilaris var. aurea of Kartesz (1994) treated as O. aurea by him in 1999.