''Coryphantha ramillosa'' is a rare species of

cactus A cactus (, or less commonly, cactus) is a member of the plant family Cactaceae, a family comprising about 127 genera with some 1750 known species of the order Caryophyllales. The word ''cactus'' derives, through Latin, from the Ancient Gre ...

known by the common names bunched cory cactus and whiskerbush. It is native to the border region between

Texas Texas (, ; Spanish language, Spanish: ''Texas'', ''Tejas'') is a state in the South Central United States, South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2 ...

in the United States and

Coahuila Coahuila (), formally Coahuila de Zaragoza (), officially the Free and Sovereign State of Coahuila de Zaragoza ( es, Estado Libre y Soberano de Coahuila de Zaragoza), is one of the 32 states of Mexico. Coahuila borders the Mexican states of N ...

in Mexico. Because it was believed to be rare and threatened by a number of processes, it was federally listed as a threatened species of the United States in 1979.USFWS
Determination that ''Coryphantha ramillosa'' and ''Neolloydia mariposensis'' are threatened species.
''Federal Register'' November 6, 1979. The range and abundance of this plant are not well known, especially within Mexico, and it may not be as uncommon as was thought in 1979. The cactus occurs in at least seven locations in Texas, several being within the bounds of

Big Bend National Park Big Bend National Park is an American national park located in West Texas, bordering Mexico. The park has national significance as the largest protected area of Chihuahuan Desert topography and ecology in the United States, and was named after ...

. One of the most recent estimates of abundance in Texas is 5,000 to 10,000 individuals in two counties. The range of appropriate habitat in Mexico covers 2.5 times the amount of land as in Texas.''Coryphantha ramillosa''.
Center for Plant Conservation.''Coryphantha ramillosa''.
The Nature Conservancy. Many of the plants are located in remote areas, which helps protect them from people. A major threat to the species is harvesting by cactus enthusiasts and dealers.''Coryphantha ramillosa''.
Texas Parks and Wildlife. This cactus is generally spherical or cylindrical in shape, and unbranched. It grows up to about 9.5 centimeters long and is textured with protruding areoles up to 2 centimeters tall. The areoles bear curving spines, the central one thick, dark, and up to 4.3 centimeters in length. The smaller spines are light in color, often white. The showy flower occurs at the apex of the cactus body and measures up to 6.5 centimeters long. Its

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 are pink, lightening to pale pink or white near the center, and sometimes with darker midstripes. The rounded fruit is pale to dark green, fleshy and juicy and 1 or 2 centimeters long.''Coryphantha ramillosa''.
Flora of North America. The plant blooms in the summer, with an extended blooming period when rainfall is higher. The cactus occurs in

desert scrub Deserts and xeric shrublands are a biome defined by the World Wide Fund for Nature. Deserts and xeric (ancient Greek xērós, “dry") shrublands form the largest terrestrial biome, covering 19% of Earth's land surface area. Ecoregions in this h ...

habitat, generally in dry, rocky, barely accessible areas where few other plants grow. 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 wh ...

. The plant is being propagated and studied at

Desert Botanical Garden Desert Botanical Garden is a botanical garden located in Papago Park, at 1201 N. Galvin Parkway in Phoenix, central Arizona. Founded by the Arizona Cactus and Native Flora Society in 1937 and established at this site in 1939, the garden now ha ...

Phoenix, Arizona Phoenix ( ; nv, Hoozdo; es, Fénix or , yuf-x-wal, Banyà:nyuwá) is the capital and most populous city of the U.S. state of Arizona, with 1,608,139 residents as of 2020. It is the fifth-most populous city in the United States, and the o ...

.Rice, K. C
The search for ''Coryphantha ramillosa''.
''Endangered Species Bulletin'' July–August 2002.

References

External links

USDA Plants Profile for ''Coryphantha ramillosa''
{{Taxonbar, from=Q150200 ramillosa Cacti of Mexico Cacti of the United States Flora of the Chihuahuan Desert Flora of Coahuila Flora of Texas Endangered biota of Mexico Endangered flora of the United States