botanical nomenclature Botanical nomenclature is the formal, scientific naming of plants. It is related to, but distinct from taxonomy (biology), taxonomy. Plant taxonomy is concerned with grouping and classifying plants; Botany, botanical nomenclature then provides na ...

, variety (abbreviated var.; in ) is a

taxonomic rank In biology, taxonomic rank (which some authors prefer to call nomenclatural rank because ranking is part of nomenclature rather than taxonomy proper, according to some definitions of these terms) is the relative or absolute level of a group of or ...

below that of

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), ...

and

subspecies In Taxonomy (biology), biological classification, subspecies (: subspecies) is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (Morphology (biology), morpholog ...

, but above that of form. As such, it gets a three-part infraspecific name. It is sometimes recommended that the subspecies rank should be used to recognize geographic distinctiveness, whereas the variety rank is appropriate if the taxon is seen throughout the geographic range of the species.

Example

The pincushion cactus, ''

Escobaria vivipara ''Pelecyphora vivipara'' is a species of cactus known by several common names, including spinystar, viviparous foxtail cactus, pincushion cactus and ball cactus. It is native to North America, where certain varieties can be found from Mexico to C ...

'', is a wide-ranging variable species occurring from Canada to Mexico, and found throughout New Mexico below about . Nine varieties have been described. Where the varieties of the pincushion cactus meet, they intergrade. The variety ''Escobaria vivipara'' var. ''arizonica'' is from Arizona, while ''Escobaria vivipara'' var. ''neo-mexicana'' is from New Mexico.

Definitions

The term is defined in different ways by different authors. However, the International Code of Nomenclature for Cultivated Plants, while recognizing that the word "variety" is often used to denote "

cultivar A cultivar is a kind of Horticulture, cultivated plant that people have selected for desired phenotypic trait, traits and which retains those traits when Plant propagation, propagated. Methods used to propagate cultivars include division, root a ...

", does not accept this usage. Variety is defined in the code as follows: "Variety (varietas) the category in the botanical nomenclatural hierarchy between species and form (forma)". The code acknowledges the other usage as follows: "term used in some national and international legislation for a clearly distinguishable taxon below the rank of species; generally, in legislative texts, a term equivalent to cultivar. See also: cultivar and variety (varietas)". A variety will have an appearance distinct from other varieties, but will hybridize freely with those other varieties.

Other nomenclature uses

* In plant breeding nomenclature, at least in countries that are signatory to the UPOV Convention, " variety" or "plant variety" is a legal term. * In

zoological nomenclature The International Code of Zoological Nomenclature (ICZN) is a widely accepted convention in zoology that rules the formal scientific naming of organisms treated as animals. It is also informally known as the ICZN Code, for its formal author, t ...

, the only allowed rank below that of species is that of

. A name that was published before 1961 as that of a variety is taken to be the name of a subspecies. A name published after 1960 as that of a variety does not formally exist. In zoology, forms and morphs are used informally if needed, but are unregulated by the '' ICZN''. * The bacteriological nomenclature uses the term subspecies. Some names were published as "varieties" before 1992 but the terminology is now disallowed; names that were published as varieties are taken to be published as subspecies. * In

viticulture Viticulture (, "vine-growing"), viniculture (, "wine-growing"), or winegrowing is the cultivation and harvesting of grapes. It is a branch of the science of horticulture. While the native territory of ''Vitis vinifera'', the common grape vine ...

nomenclature, what is referred to as " grape varieties" are in reality

s according to usage in the '' International Code of Nomenclature for Cultivated Plants'' or " plant varieties" in the legal sense rather than botanical taxonomy varieties, since they are propagated by cuttings and have properties that are not stable under

sexual reproduction Sexual reproduction is a type of reproduction that involves a complex life cycle in which a gamete ( haploid reproductive cells, such as a sperm or egg cell) with a single set of chromosomes combines with another gamete to produce a zygote tha ...

. However, usage of the term variety is so entrenched in viticulture that a change to cultivar is unlikely.

References

Bibliography

* * {{Taxonomic ranks Variety Plant taxonomy