''Hylocereus'' is a former

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 epiphytic

cacti 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 Gree ...

, often referred to as night-blooming cactus (though the term is also used for many other cacti). Several

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriat ...

previously placed in the genus have large edible

fruit In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in partic ...

s, which are known as pitayas, pitahayas or dragonfruits. In 2017, a

molecular phylogenetic Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...

study confirmed an earlier finding that the genus ''Hylocereus'' was nested within ''Selenicereus'', so all the species of ''Hylocereus'' were transferred to '' Selenicereus''.

Description

The species previously placed in the genus ''Hylocereus'' grow hanging, climbing or epiphytic. They are freely branched, shrubby plants that form aerial roots and become very large with a height of 10 m or more. The green, often glaucous shoots are usually terete or triangular.

Taxonomy

In the 1994 classification of the International Cactaceae Systematics Group of the

International Organization for Succulent Plant Study The International Organization for Succulent Plant Study (IOS) describes itself as a "non-governmental organization promoting the study and conservation of succulent and allied plants and encouraging collaboration among scientists and curators ...

, the genus ''Hylocereus'' was one of the six genera of the tribe Hylocereeae., p. 101 A 2011 study of the molecular phylogeny of the Cactaceae concluded that neither the tribe nor the genus was

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gr ...

(i.e. neither comprised all the descendants of a common ancestor). Two species of ''Hylocereus'' formed a

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English ter ...

with two species of '' Selenicereus'', suggesting that the genera were not distinct. This result was confirmed in a larger study in 2017, and all the species of ''Hylocereus'' were transferred to ''Selenicereus''.

Species

Species that were placed in the genus in 2012 that are now placed in ''Selenicereus'' include the following. *''Hylocereus calcaratus'' → '' Selenicereus calcaratus'' *''Hylocereus costaricensis'' → '' Selenicereus costaricensis'' *''Hylocereus escuintlensis'' → '' Selenicereus escuintlensis'' *''Hylocereus megalanthus'' → '' Selenicereus megalanthus'' *''Hylocereus monacanthus'' → '' Selenicereus monacanthus'' *''Hylocereus minutiflorus'' → '' Selenicereus minutiflorus'' *''Hylocereus ocamponis'' → '' Selenicereus ocamponis'' *''Hylocereus setaceus'' → '' Selenicereus setaceus'' *''Hylocereus stenopterus'' → '' Selenicereus stenopterus'' *''Hylocereus triangularis'' → '' Selenicereus triangularis'' *''Hylocereus trigonus'' → '' Selenicereus trigonus'' *''Hylocereus undatus'' → '' Selenicereus undatus''

References

CactiGuide: ''Hylocereus''
{{Taxonbar, from1=Q133960, from2=Q14928251 Historically recognized angiosperm genera Cacti of North America Night-blooming plants

Description

Taxonomy

Species

See also

References