''Acharagma'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of two

cactus A cactus (: cacti, cactuses, or less commonly, cactus) is a member of the plant family Cactaceae (), a family of the order Caryophyllales comprising about 127 genera with some 1,750 known species. The word ''cactus'' derives, through Latin, ...

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

from northern

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

Description

These

cacti A cactus (: cacti, cactuses, or less commonly, cactus) is a member of the plant family Cactaceae (), a family of the order Caryophyllales comprising about 127 genera with some 1,750 known species. The word ''cactus'' derives, through Latin, ...

are usually solitary but sometimes occur in small clusters. The globose stems tend to be about 3–7 cm in diameter. The ribs have tubercles, with ungrooved

areole In botany, areoles are small light- to dark-colored bumps on cactus, cacti out of which grow clusters of Thorns, spines, and prickles, spines. Areoles are important diagnostic features of cactus, cacti, and identify them as a family distinct fr ...

s. The flowers are at the stem tips, and range from cream to pink and yellow. The genus is of relatively recent creation, the species originally being described as part of ''

Escobaria ''Pelecyphora'', pincushion cactus or foxtail cactus is a genus of cactus, cacti, comprising 20 species. They originate from Mexico and the United States. Common species include the Missouri foxtail cactus ''Pelecyphora missouriensis, P. missour ...

'', although recognized as a separate section by

Nigel Taylor Nigel Paul Taylor (born 1956) is a British botanist. He mainly focuses on the study of cacti. Taylor has been director of the Singapore Botanic Gardens since September 2011. He was previously curator of the Kew Gardens in London London is t ...

in 1983, and raised to a genus by

Charlie Glass Charles Edward Glass (24 May 1934 – 23 February 1998) was an American horticulturalist and plant collector. Together with his best friend, Bob Foster, Glass collected and scientifically described dozens of cacti species, edited the '' Cactus ...

in 1998.

Species

Plants of the World Online Plants of the World Online (POWO) is an online taxonomic database published by the Royal Botanic Gardens, Kew. History Following the Convention on Biological Diversity, the Royal Botanic Gardens in Kew launched Plants of the World Online i ...

accepts two species. A third possible species, ''A. huasteca'', described in 2011, is considered to be a synonym of ''Acharagma roseanum'' subsp. ''galeanense''.

References

* Edward F. Anderson, ''

The Cactus Family ''The'' is a grammatical article in English, denoting nouns that are already or about to be mentioned, under discussion, implied or otherwise presumed familiar to listeners, readers, or speakers. It is the definite article in English. ''The ...

'' (Timber Press, 2001), pp. 108–109 * Zsolt Elhart, CactusWorld 29(2): 105. 2011

External links

* * Cactoideae genera Cacti of Mexico Endemic flora of Mexico Flora of Coahuila Cactoideae {{Cactus-stub