''Pediocactus despainii'' is a rare species of cactus known by the common names Despain's cactus and San Rafael cactus. It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to the state of

Utah Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to it ...

in the United States, where it is limited to the

San Rafael Swell The San Rafael Swell is a large geologic feature located in south-central Utah, United States about west of Green River. The San Rafael Swell, measuring approximately , consists of a giant dome-shaped anticline of sandstone, shale, and limeston ...

Emery County Emery County is a county in east-central Utah, United States. As of the 2010 United States Census, the population was 10,976. Its county seat is Castle Dale, and the largest city is Huntington. History Prehistory Occupation of the San Rafael ...

, Utah.''Pediocactus despainii''.
Center for Plant Conservation. There are two populations totalling about 6000 individuals.''Pediocactus despainii''.
The Nature Conservancy. It is threatened by a number of human activities.USFWS
Determination of End. Status for ''Pediocactus despainii'' (San Rafael Cactus).
''Federal Register'' September 16, 1987. It is a federally listed

endangered species An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inv ...

of the United States. This cactus was discovered in 1978 by Kim Despain and described to science in 1980. It has sometimes been treated as a subspecies or variety of ''

Pediocactus bradyi ''Pediocactus bradyi'' is a very rare species of cactus known by the common names Brady's pincushion cactus, Brady's hedgehog cactus, and Marble Canyon cactus. It is endemic to Arizona in the USA, where it is restricted to Marble Canyon in Coconi ...

'' but is not generally accepted as such. It occurs generally near to its closest relative, ''

Pediocactus winkleri ''Pediocactus bradyi'' subsp. ''winkleri'', commonly known as Winkler's cactus or Winkler's pincushion cactus, is a small cactus endemic to the state of Utah in the United States. It is known only from Emery and Wayne Counties. Description ''P ...

''.''Pediocactus despainii''.
Flora of North America. This egg-shaped or somewhat rounded cactus grows up to 6 centimeters tall and about 9 wide, and generally has no branches. It shrinks in size and disappears under the ground in dry and cold times, making it hard to find for most of the year. Each

areole In botany, areoles are small light- to dark-colored bumps on cacti out of which grow clusters of spines. Areoles are important diagnostic features of cacti, and identify them as a family distinct from other succulent plants. Gordon Rowley - W ...

bears up to 15 smooth white spines each measuring a few millimeters long. The plant produces a flower up to 2.5 centimeters long and wide with yellowish or pinkish

tepal A tepal is one of the outer parts of a flower (collectively the perianth). The term is used when these parts cannot easily be classified as either sepals or petals. This may be because the parts of the perianth are undifferentiated (i.e. of very ...

s, the outer ones with purple midstripes. The fruit is green ripening reddish and measures about a centimeter long and wide. This cactus grows in the San Rafael Swell, a unique geologic feature in central Utah. It is an area with many rare native plants and has a high rate of endemism. The substrate is

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

and

siltstone Siltstone, also known as aleurolite, is a clastic sedimentary rock that is composed mostly of silt. It is a form of mudrock with a low clay mineral content, which can be distinguished from shale by its lack of fissility.Blatt ''et al.'' 1980, p ...

soil originating in the

Carmel Carmel may refer to: * Carmel (biblical settlement), an ancient Israelite town in Judea * Mount Carmel, a coastal mountain range in Israel overlooking the Mediterranean Sea * Carmelites, a Roman Catholic mendicant religious order Carmel may also ...

and

Moenkopi Formation The Moenkopi Formation is a geological formation that is spread across the U.S. states of New Mexico, northern Arizona, Nevada, southeastern California, eastern Utah and western Colorado. This unit is considered to be a group in Arizona. Part ...

s. The habitat is

grassland A grassland is an area where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur natur ...

with some

juniper Junipers are coniferous trees and shrubs in the genus ''Juniperus'' () of the cypress family Cupressaceae. Depending on the taxonomy, between 50 and 67 species of junipers are widely distributed throughout the Northern Hemisphere, from the Arcti ...

s and

pinyon pine The pinyon or piñon pine group grows in southwestern North America, especially in New Mexico, Arizona, and Utah. The trees yield edible nuts, which are a staple food of Native Americans, and widely eaten as a snack and as an ingredient in New ...

s. Threats to this species include

poaching Poaching has been defined as the illegal hunting or capturing of wild animals, usually associated with land use rights. Poaching was once performed by impoverished peasants for subsistence purposes and to supplement meager diets. It was set a ...

off-road vehicle An off-road vehicle, sometimes referred to as an overland or adventure vehicle, is considered to be any type of vehicle which is capable of driving on and off paved or gravel surface. It is generally characterized by having large tires with dee ...

use,

gypsum Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula . It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, blackboard or sidewalk chalk, and drywall. ...

mining, and

petroleum exploration Hydrocarbon exploration (or oil and gas exploration) is the search by petroleum geologists and geophysicists for deposits of hydrocarbons, particularly petroleum and natural gas, in the Earth#Crust, Earth using petroleum geology. Exploration m ...

References

External links

USDA Plants Profile
{{Taxonbar, from=Q14626455 Cacti of the United States Flora of Utah Endemic flora of the United States Plants described in 1980 despainii