 | This article needs additional citations for verification. (August 2018) |
| Cactoideae | |
|---|---|
| |
| Mammillaria elongata | |
Scientific classification 
| |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Order: | Caryophyllales |
| Family: | Cactaceae |
| Subfamily: | Cactoideae Eaton |
| Tribes or clades | |
The Cactoideae are the largest subfamily of the cactus family, Cactaceae, and are widely distributed throughout the Americas. Cactaceae is the 5th most endangered plant or animal family evaluated globally by the International Union for Conservation of Nature.[1] Around 80% of cactus species belong to this subfamily.[2] The genera of the Cactoideae are characterized by microscopic foliage leaves. All photosynthesis occurs in shoot cortex cells covered by a persistent epidermis and stomata. Another important characteristic of this subfamily is ribbed stems, which enable the inner cortex to expand radially without breaking the shoot surface to absorb large quantities of water.[3]
As of August 2018[update], the internal classification of the family Cactaceae remained uncertain and subject to change. A classification incorporating many of the insights from the molecular studies was produced by Nyffeler and Eggli in 2010.[4] Various revisions have been published since, e.g. to the tribe Hylocereeae and the tribe Echinocereeae.[5] Classifications remained uncertain as of March 2019[update].
- ^ Goettsch, Bárbara; Hilton-Taylor, Craig; Cruz-Piñón, Gabriela; Duffy, James P.; Frances, Anne; Hernández, Héctor M.; Inger, Richard; Pollock, Caroline; Schipper, Jan; Superina, Mariella; Taylor, Nigel P.; Tognelli, Marcelo; Abba, Agustín M.; Arias, Salvador; Arreola-Nava, Hilda J. (2015-10-05). "High proportion of cactus species threatened with extinction". Nature Plants. 1 (10): 1–7. doi:10.1038/nplants.2015.142. hdl:11336/11280. ISSN 2055-0278.
- ^ Arthur C. Gibson; Park S. Nobel (11 October 1990). The Cactus Primer. Harvard University Press. p. 23. ISBN 9780674089914.
- ^ Mauseth, J. D. (2006). Structure–function relationships in highly modified shoots of Cactaceae. Annals of Botany, 98(5), 901-926.
- ^ Nyffeler, R. & Eggli, U. (2010). "A farewell to dated ideas and concepts: molecular phylogenetics and a revised suprageneric classification of the family Cactaceae". Schumannia. 6: 109–149. doi:10.5167/uzh-43285. S2CID 89650660.
- ^ Korotkova, Nadja; Borsch, Thomas & Arias, Salvador (2017). "A phylogenetic framework for the Hylocereeae (Cactaceae) and implications for the circumscription of the genera". Phytotaxa. 327 (1): 1–46. doi:10.11646/phytotaxa.327.1.1.