# Terminology for white Cattleya flowers



## terryros (May 7, 2022)

Nudged by DrLeslieEe, I searched for references on terminology for Cattleya flower color variation, particularly related to white flowers. The following reference was succinct, had pictures, and although directed at Paphiopedilum, the terms apply equally to Cattleya: Braem, Guido J. Notes on albinism. Australian Orchid Review 2014:2-12. I attached a PDF of the chapter.

Official orchid descriptions have always been in Latin. Early botanists made liberal use of the term “varietas” (usually abbreviated var.) after a species name to identify differences between related plants. Some of the Cattleya species discovered after labiata were even, for a time, named as var. of labiata and color variations within a species were also identified with var. (e.g., Cattleya labiata var. alba). Some species’ color variations were noted by var. with a prominent person’s name (e.g., Cattleya mossiae var. reineckiana to indicate a semialba mossiae).

Botanical experts evolved to think that var. should not be used simply for color variation within a species. Some proposed that “forma” (usually abbreviated fma.) could be used instead. Eventually, even fma. was dropped by some botanists and growers and the color adjective for later species was just appended after the species name, (e.g., Cattleya jenmanii semialba).

There are three types of orchid flower pigments: anthocyanins (create perceived colors of blue, mauve, lavender, purple, magenta, and red), carotenes (yellow and orange colors), and chlorophylls (green colors). Colors are separately encoded genetically for the sepals, petals, inner labellum, and outer labellum. A pure white flower with no anthocyanin, carotene, or chlorophyl in the sepals, petals, and labellum is rare in Cattleya. Most Cattleyas with white sepals and petals have residual carotenes or chlorophyll in part of the labellum.

*Albino: *denotes a plant with either leaves or flowers that lack anthocyanin pigments. The orchid world seems to have decided not to use this broad term but instead looked for terms that would focus just on the flowers lacking anthocyanins.

The most widely used terms are *alba, album, or albus, *depending on the grammatical gender of the orchid genus. For example, Cattleya is grammatically feminine, so the correct term is alba. Paphiopedilum is gender neutral and the correct term is album.

*Albida/albidum/albidus *are alternate terms that were used infrequently. The terms *albifora/albiflorum/albiflorus* are also infrequently used synonyms for flowers lacking any anthocyanin pigment.

*Albescens, albinistic: *These terms mean the same thing as *alba/albus/album but* are sometimes used incorrectly to describe flowers that “almost made it to alba”. However, the definition of alba/albus/album is strict. There should be no evidence of anthocyanin anywhere on the flower. There is no official term for a flower that is “almost alba”.

Some alba/album/albus flowers can have strong carotenoid or chlorophyl pigmentation of sepals or petals. The resulting flowers may be green to yellow. The plants can still be correctly called alba/album/albus but particularly with yellow, the term “flava/flavum/falvus” is used. I haven’t found a Latin word to use when the predominant color ends up being green


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## My Green Pets (May 9, 2022)

Thanks for you research. Interesting how albescens has come to mean what it does.
On a separate note, have you ever happened upon the reason that the latin for blue, caerulea, somehow became coerulea in modern taxonomy? I can't find any evidence that the word coerulea even exists in Latin.


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## Ozpaph (May 10, 2022)

I understand people can add a cultivar name of their choice which doesnt have to abide by taxonomic correctness. eg C jenmanii 'semialba' could be a cultivar name, not an accurate taxonomic descriptor..................Because colloquially others know that means a white petalled flower with coloured lip.


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## terryros (May 10, 2022)

My Green Pets said:


> Thanks for you research. Interesting how albescens has come to mean what it does.
> On a separate note, have you ever happened upon the reason that the latin for blue, caerulea, somehow became coerulea in modern taxonomy? I can't find any evidence that the word coerulea even exists in Latin.


What I find is that Linnaeus used the term caerulea but over time coerulea started to be used. Many plants originally named by Linneaus carry the caerulea label.


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## terryros (May 10, 2022)

Ozpaph said:


> I understand people can add a cultivar name of their choice which doesnt have to abide by taxonomic correctness. eg C jenmanii 'semialba' could be a cultivar name, not an accurate taxonomic descriptor..................Because colloquially others know that means a white petalled flower with coloured lip.


I think you are free to choose a cultivar name. I think it would be ‘Semialba’ capitalized. The question would be how much confusion this creates. I think if you wanted your cultivar to be noticed or remembered you would choose a more distinct name.


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## Ozpaph (May 10, 2022)

Of course, but people are lazy and want to sell plants, so they do what they want.


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## My Green Pets (May 10, 2022)

That's good to know. I wonder if the Latin letter æ was mistaken for œ at some point.



terryros said:


> What I find is that Linnaeus used the term caerulea but over time coerulea started to be used. Many plants originally named by Linneaus carry the caerulea label.


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