The orchid family, Orchidaceae, known for its enormous size, has been divided into five Subfamilies and then further into Tribes and Subtribes. The less official designation of an “orchid alliance” is a group of closely related plants, at any taxonomic rank, but usually at the rank of genus or species. Orchids can bear perplexing names with unusual naming conventions, causing some confusion among enthusiasts. Here are the basics of understanding an orchid's name.
Orchids species that occur in nature are given botanical names that resemble those of other plants, with each species identified by its genus and specific epithet. Genus is capitalized and italicized and the specific epithet is italicized.
Example: Dendrobium bigibbum
Plants that are very similar but with some horticulturally significant variation from the species type may be recognized as a subspecies (subsp.), variety (var.) or form (f.) of the species, in declining order of distinctiveness. Notice that the botanical variety is italicized, and the abbreviation var. is not. Both are in lower case font.
Dendrobium bigibbum var. compactum
So far this naming methodology should seem familiar, following the rules of the binomial system devised by Carl Linnaeus in the 18th century. But what is happening when we see a name like this:
Dendrobium Spring Bird 'Kurashiki’?
Most of the hybrid orchids we encounter are created by breeders. They may occur when two species, two hybrids, two related genera, or any combination of these is crossed to create new plant types.
The complex name Dendrobium Spring Bird 'Kurashiki’ includes
The grex name is capitalized with no italics, may contain more than one word and is in a living language. It is essentially a non-"latin" name for this artificially created hybrid species of Dendrobium. The cultivar name is capitalized and has single quotes.
The grex Spring Bird is the name applied to all the hybrid outcomes of a specific set of two orchid parents. The grex name is established when the hybridizing breeder makes an application to the Royal Horticultural Society ("RHS"), the Registrar for Orchidaceae, specifying the parents of its new hybrid orchid and is thereafter applied to all outcomes of those parents. A combination of two orchid species is referred to as a primary hybrid while the combination of two hybrid parents, or one species and one hybrid parent, is called a complex hybrid.
Like human progeny, not all outcomes of this particular cross will be identical. Outcomes of merit resulting from hybridizations may be given a cultivar name and then vegetatively reproduced to create genetically identical orchids with desirable characteristics. For example, Dendrobium Spring Bird 'Kurashiki' and Dendrobium Spring Bird 'Tsuyama' are both cultivars from the Dendrobium Spring Bird hybridization of Dendrobium Demitasse and Dendrobium Sweet Love.
It is not unusual to see a hybrid orchid cultivar tagged without the use of the grex name. Dendrobium ‘Kurashiki’ is the same plant as Dendrobium Spring Bird 'Kurashiki' but with some helpful information about parentage omitted in a shorthand version of the name.
If the hybrid orchid has not had a name registered with the RHS, it can be named by listing the parent orchids separated by an × which is called a hybrid formula. If both parents are of the same genus, the name of the genus can be used just once.
Example: Phalaenopsis Taida Leopard Princess × Taisuco Firebird
Sometimes this hybrid naming format listing the parent plants is also used for registered hybrids as an alternative to the grex name.
In addition to hybridizing orchids within a genus, it is possible for orchid breeders to hybridize orchid plants from two or more different natural genera to create an intergeneric hybrid. This artificial genus is given a new condensed name that is often a combination of the names of the contributing genera.
Example: all intergeneric hybrids of Brassavola and Cattleya orchids are named Brassocattleya.
Intergeneric hybrids with contributions from numerous (four or more, though occasionally three) orchid genera are named for or by the originator and end in -ara. A List of all Orchid Genera and Intergeneric Hybrids (with their component genera) is available as a PDF file from the Royal Horticultural Society. The names may also be expressed with an x preceding the name to indicate an intergeneric hybrid, though the condensed name already signals it.
Example: Bardendrum Nanboh Pixy 'Cherry Moon' or × Bardendrum Nanboh Pixy 'Cherry Moon'
Orchid hybrids also occur in nature where closely related plants share a habitat. Naturally occurring hybrid orchids, collected in the wild, are indicated by a newly created name with a × in it.
Example: Dendrobium × superbiens is a natural hybrid of two species (Dendrobium bigibbum and Dendrobium discolor).
Sometimes, the × is left out of the name. Dendrobium superbiens is the same plant as Dendrobium × superbiens.
You may also encounter an orchid tagged with a trade name.
Example: Phalaenopsis SUMMER SNOW
This name is not the officially registered name for this orchid hybrid, but a marketing name assigned by the seller that does not specify information regarding parentage. The trade name is expressed in all capital letters, with initial capitals in slightly larger font size.
Abbreviations may be used in orchid names for both natural and hybrid genera and there are standards for doing so. Like the long-form name, these abbreviations are capitalized and italicized.
Examples:
A List of Standard Abbreviations for Natural and Hybrid Generic Names is available as a PDF file from the RHS.
Finally, if the orchid cultivar has gained an award by an orchid society then this can be indicated at the end of the name, e.g. AD/AOS for Award of Distinction from the American Orchid Society. Award names and the names of the awarding societies are abbreviated in all capital letters without periods.
Example: Vanda Will Riley ‘Crownfox Raspberry’ AM/AOS indicates that this orchid has received an Award of Merit from the American Orchid Society.
A more detailed discussion of orchid nomenclature can be found in The Handbook on Orchid Nomenclature and Registration, prepared by the International Orchid Commission with the cooperation of the Royal Horticultural Society.
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