''Turbinicarpus'' is a
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...
of very small to medium-sized
cacti, which inhabit the north-eastern regions of
Mexico
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...
, in particular the states of
San Luis PotosÃ,
Guanajuato,
Nuevo León,
Querétaro,
Hidalgo
Hidalgo may refer to:
People
* Hidalgo (nobility), members of the Spanish nobility
* Hidalgo (surname)
Places
Mexico
* Hidalgo (state), in central Mexico
* Hidalgo, Coahuila, a town in the north Mexican state of Coahuila
* Hidalgo, Nuevo Leà ...
,
Coahuila,
Tamaulipas
Tamaulipas (), officially the Free and Sovereign State of Tamaulipas ( es, Estado Libre y Soberano de Tamaulipas), is a state in the northeast region of Mexico; one of the 31 states which, along with Mexico City, comprise the 32 Federal Entiti ...
and
Zacatecas
, image_map = Zacatecas in Mexico (location map scheme).svg
, map_caption = State of Zacatecas within Mexico
, coordinates =
, coor_pinpoint =
, coordinates_footnotes =
, subdivision_type ...
.
Taxonomy
The taxon was first proposed by
Curt Backeberg Curt Backeberg (2 August 1894 in Lüneburg, Germany – 14 January 1966) was a German horticulturist especially known for the collection and classification of cacti.
Biography
He travelled extensively through Central and South America, and publis ...
as ''Strombocactus'' subgenus ''Turbinicarpus''. It was elevated to a genus in 1937 by
Franz Buxbaum and Backeberg.
[ The ]circumscription
Circumscription may refer to:
*Circumscribed circle
* Circumscription (logic)
*Circumscription (taxonomy)
*Circumscription theory, a theory about the origins of the political state in the history of human evolution proposed by the American anthrop ...
of ''Turbinicarpus'' has been described as "remarkably unstable", with species regularly transferred to other genera.[ Its taxonomic history is often mixed with that of other genera like '']Echinocactus
''Echinocactus'' is a genus of cacti in the subfamily Cactoideae. The generic name derives from the Ancient Greek εχινος (''echinos''), meaning "spiny," and ''cactus''. It and ''Ferocactus'' are the two genera of barrel cactus. Members ...
'', '' Echinomastus'', '' Gymnocactus'', ''Mammillaria
''Mammillaria'' is one of the largest genera in the cactus family (Cactaceae), with currently 200 known species and varieties recognized. Most of the mammillaria are native to Mexico, but some come from the southwest United States, the Caribbea ...
'', '' Neolloydia'', '' Normanbokea'', '' Pediocactus'', '' Pelecyphora'', '' Strombocactus'', ''Thelocactus
''Thelocactus'' is a genus of flowering plants in the cactus family Cactaceae. Members of the genus are native to the arid lands of Central and Northern Mexico.
Description
''Thelocactus'' species are globe-shaped, short and cylindrical. They ...
'' and '' Toumeya'', as the results of almost two centuries of constant evolution in the understanding of the affinities and relationships inside the family Cactaceae. A genus revision by Davide Donati in 2003, and again in 2004 with Carlo Zanovello, was based on a wide range of characters. At the end of that study, '' Rapicactus'' was considered a distinct genus from ''Turbinicarpus''. The genus ''Turbinicarpus'' was subdivided in two subgenera at the light of the results of the DNA analysis, and into many series because of the ontogeny of the spination.[ The broad circumscription of ''Turbinicarpus'' was recognized as ]polyphyletic
A polyphyletic group is an assemblage of organisms or other evolving elements that is of mixed evolutionary origin. The term is often applied to groups that share similar features known as homoplasies, which are explained as a result of conver ...
by Hunt in 2016.[ A ]phylogenetic
In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...
study published in 2019 showed that both '' Kadenicarpus'' and ''Rapicactus'' were distinct from a more narrowly circumscribed and so monophyletic ''Turbinicarpus'':[
]
Species
, Plants of the World Online accepted the following species and hybrids:[
]
Natural hybrids
Synonymy
The following genera haven been brought into synonymy with ''Turbinicarpus'':
*''Gymnocactus'' Backeb.
*''Normanbokea'' Kladiwa & Buxb.
Ecology
These succulent plants grow mostly on limestone soil (never on volcanic soil), at altitudes between 300 and 3300 metres above sea level.
''Turbinicarpus'' species are usually confined to specific habitats, generally hostile for the majority of plants, mostly in very drained rocky areas, composed of limestone, sandstone, schist (neutral or alkaline), or in very acidic and humiferous understorey, or in gypsum veins, sometimes so pure that they are almost white.
In particular, ''Turbinicarpus sensu stricto'' is adapted to extreme niches: more than 80% of the species grow in rock cracks or among the pebbles beneath them, where enough dust has accumulated to enable root development. It would seem almost impossible that plants so small could survive in such an environment, however in those species that inhabit dry and exposed areas, the root is very thick, becoming a taproot and acting like an anchor on the slopes but, more important, as water storage for the dry periods, capable of significantly retracting into the ground so that the stem is less exposed to the sun; the spines are often changed to adopt a very papery structure, capable of absorbing good quantities of water. Furthermore, the general look is extremely mimetic, thanks to the epidermis colour and the interlacing spines, guaranteeing a certain protection from eventual herbivores.
References
* Edward F. Anderson, ''The Cactus Family'' (Timber Press, 2001), pp. 665–673
*Grupo San Luis, ''The Genus Turbinicarpus in San Luis Potosì'' (Ed. Cactus&Co, 2004)
External links
"Alkaloids and why Turbinicarpus sp. contain them" (Turbinicarpus Information Exchange)
{{Taxonbar, from=Q137209
Medicinal plants
Cactoideae genera