General Plant Naming Conventions

Plant name sub-divisions

Plant Naming Rules

Latin names - what do they mean?

How do you pronounce the Latin names?

What about hybrid plant names?

Plant name sub-divisions.

The following name parts exist and are in common use where necessary depending on the break-down of plant variations.

Family – a closely related group of genera. All family names are easily recognised because they all have the ending 'aceae' (meaning "resemblance"). The botanical code specifies that a family name is formed from the type genus with the 'aceae' appended conveniently.

Genus – a group of plants having common characteristics distinct from those of other genera, usually containing some or many species and being one of a series constituting a taxonomic family.

Species (abbrev. sp.) – a class having some common characteristics.

Sub-species (abbrev. ssp.) – a category below a species, usually a fairly permanent geographically isolated variation of the species.

Variety (abbrev. var.) – an individual or group, usually fertile and breed true from seed, within the species to which it belongs, but differing from the species type in some qualities – a natural variation.

Form (abbrev. f.) – a plant displaying an inherited characteristic differing from the typical species or variety. Not sufficiently stable or marked to justify the rank of 'variety'.

Cultivar (abbrev. cv.) – a man-made plant variety of a species or hybrid, produced by selective breeding. A cultivar name begins with a capital letter and is not italicised or underlined. Each additional word must start with a capital letter (except for words like "of" or "the"). Other methods of displaying cultivar names are permitted, but the method described here will be used in VCPS publications.

Eg.  Sarracenia X moorei cv. 'Marston Clone'.

Affinis (abbrev. aff.) – having affinity with. When the plant may be an extreme variant or hybrid the abbreviation "aff." is placed before the specific epithet. The plant may be close to the named species but does not agree sufficiently with descriptions to allow a definite identification.

Plant Naming Rules.

The following rules are as per the book Plant Names 'A guide to Botanical Nomenclature' (Lumley and Spencer, 1995).

1. All genus names must commence with an upper-case letter, followed by lower-case letters, and must always be printed in italics (or underscored where italics are unavailable). The genus abbreviations must be an upper-case letter and must be printed in italics. Genus abbreviations can be used where the genus name has been used previously in the text, and is not at the beginning of a sentence.

2. All officially recognised species, sub-species, varieties, and form names must consist of only lower-case letters and must be printed in italics (or underscored). The sub-division names, or their abbreviations, must never be italicised – eg. Drosera binata ssp. multifida f. extrema.

3. Plants having probable species status, but not yet officially recognised as such, have the interim species name enclosed in single quotes and not italicised, and are preceded by the 'sp.' abbreviation, eg. Pinguicula sp. 'Pico de Orizaba'.

4. Natural hybrid names are printed in italic characters and Latinised, as for species. The hybrid epithet is preceded by a 'X' (small caps) – eg. Drosera X badgerupii.

5. Man-made hybrid and cultivar names are enclosed in single quote characters, printed in normal lettering, and each word starts with a capital letter – not preceded by an 'X'.

Eg. Nepenthes 'Dreamy Koto' or Nepenthes 'Hareliana' cv. 'Boca Rose'.

6. Cultivars of species retain the botanical name of the original species.

Eg. Nepenthes thorelii cv. 'Aglow Koto'.

7. Cultivars derived from the same parents as natural hybrids retain the botanical name of the original hybrid. Cultivars of man-made hybrids retain the horticultural name of the original hybrid.

Eg. Sarracenia X excellens cv. 'Lochness' (natural hybrid cultivar)

and Drosera 'Obovata' cv. 'Clavata' (man-made hybrid cultivar).

8. In a hereditary specification for hybrids, any pair of parents for that hybrid are separated by a lower-case 'x' character and spaces. Hybrid parents are specified in parenthesised groups if necessary, where multiple groups were used in the composition of the plant.

9. In hybrid specifications any pair of parents are shown in alphabetic order or, if the female parent is known, this parent is shown first.

10. Man-made hybrid and cultivar names should not be Latinised from now on. The ones previously accepted in their Latinised name-form will remain as such to avoid the confusion of changing names, but no new ones from now on.

11. In hybrid specifications any pair of parents should be shown in alphabetic order or, if the female parent is known, it should be shown first.

12. Occasionally people wonder how you make the plural form of a genus name. For example, if you wish to discuss several Pinguicula species; do you call them Pinguiculae or Pinguiculas? The answer is that you can do neither! Pinguicula, when used in its italicised botanical code form, is the name of the genus, of which there is only one – it cannot be plural. So instead, say: "I saw many Pinguicula species".

However there is way around this problem. The references to genera can be specified as common names – not in italics and not starting with a capital letter. So, the sentences: "The tuberous droseras were flowering beautifully at Anglesea." or "You can see many pinguiculas in Mexico." are acceptable alternatives.

13. To provide some assistance with pronunciation, it is recommended, where this is phonetically possible, that every vowel is pronounced as being in a separate syllable. The letter 'Y' is classed as a sixth vowel in this instance, where is creates a distinct 'i' or 'I' sound. Latin names like leucophylla, where 'eu' has a single vowel sound, must be pronounced with that in mind. The only sensible rule to apply is that if it sounds reasonable when you hear it, and you can say it without getting your tongue severely knotted, then that will be okay.

The total naming system of plants uses two coding systems – with a combination of them where needed.

There is the Botanical Code that accommodates all the possible variations of plants that have occurred naturally in the wild. (Forget plant families and higher levels – nobody uses or remembers those names.) All the name levels occurring naturally should be printed in italics. Genus names must start with a capital letter with the rest of the name lower-case. All lower level epithets must consist of only lower-case letters. The natural hybrids are identified by having a letter 'X' (small caps) preceding the epithet.

The use of the upper-case 'X' is not recommended because it is too big. In the printing of books where the multiply sign is available (mid-way in size between 'X' and 'x') this should be used. In MS-Word the 'small caps' option of font format provides this character size, and so will be used where possible. Otherwise lower-case 'x' will be used as the natural hybrid indicator.

All the man-made hybrids and cultivars should use the Horticultural Code. In this code the names are not printed in italics. Each word in the name (no more 3 is recommended) must start with a capital letter. The names are enclosed in single quote characters. Cultivar names should be preceded by 'cv.'. Whilst the single quotes or the 'cv.' can be optional, for the desire to be consistent and not leave the reader in any doubt, it seems beneficial to always include both of them.

So, in our carnivorous plant realm we need to and now can unambiguously accommodate the following difficult combinations, using the coding systems specified in the Botanic Gardens book:

Species and species cultivars.

Eg. Nepenthes thorelii and Nepenthes thorelii cv. 'Aglow Koto'.

Species and extreme variants.

Eg. Byblis liniflora and Byblis aff. liniflora 'Noonamah, Northern Territory'.

Natural hybrids and natural hybrid cultivars.

Eg. Sarracenia X exornata and Sarracenia X exornata cv. 'Lynda Butt'.

Man-made hybrids and man-made hybrid cultivars.

Eg. Nepenthes 'Hareliana' and Nepenthes 'Hareliana' cv. 'Vittata'.

These Latinised names are difficult to understand. What do they mean?

Common names for plants, like: grass, oak, fly trap, and pitcher plant; may be fine for the masses, but when you want to study plants with any degree of seriousness you must use more 'specific' names.

Every plant and animal known to science has a scientific name. For all the plants resulting from natural evolution or natural hybridisation, these are Latin or Greek roots combined to form Latin words. Each of these individual portions of the scientific name is called an epithet. An example of such a name is Homo sapiens, which is of course is what you are. The first part of the name, 'Homo', is the name of our genus. The word genus is related to the word generic, and indicates the broad category that includes all humans and very closely related creatures. For example, all dogs, wolves, and dingos are in the genus Canis. Most 'gum trees' are in the genus Eucalyptus, and all bears are in the genus Ursus. (The Australian marsupial, the Koala, is NOT a bear – its scientific name is Phascolarctos cinereus.)

The second part of our scientific name is the species; in our case 'sapiens'. This 'specific' epithet distinguishes between the different members of a genus, for example the domestic dog (Canis familiaris) from the wolf (Canis lupus), or a human from previous species (Homo sapiens versus Homo erectus, etc). When you write a Latin name, the genus name must start with an upper-case (capital) letter and the following characters must be lower-case, while the species name must start with and consist of lower-case letters only. Finally, to be correct for all the naturally occurring life forms, you should write each epithet in italics; like Eucalyptus melliodora (our Yellow Box honey tree). On-line news-groups will try to indicate the need for italics with underscore characters – for example Felis catus or _Felis catus_ (our domestic pussy cat).

In written works, once the author has identified the genus being discussed, it is common to just use an initial; so if we were discussing Marsh Pitcher plants, we might first mention Heliamphora heterodoxa, but then say something about H. nutans or H. minor – using abbreviated epithets. This should not be done where the genus name is the first word in a sentence. A problem arises when there would be a common initial – for instance when discussing a mixture of Drosera and Drosophyllum plants. The genus names should be specified in full for each usage in such cases.

So those are the mechanics of the generic and specific parts of the names. The meanings of the names are often very interesting. The genus Utricularia is characterised by the presence of small bladders, or utricles. The specific name is usually descriptive of the plant – for example U. pentadactyla has flowers with five (penta-) finger-like (-dactyla) lobes. The species U. nova-zelandiae grows in New Zealand. Other epithets, ending with suffixes such as 'i', 'ii', or 'iana', honour some individual (usually a male), eg. Drosera slackii (named after the British horticulturist and author Adrian Slack), Sarracenia rubra ssp. wherryi (named after the American botanist Dr. E. T. Wherry), or Nepenthes rafflesiana (named after Sir Stamford Raffles, founder of Singapore). The 'ae' suffix is use when the plant is named after a woman, eg. N. burbidgeae (named after the wife of the British collector F.W. Burbidge). When the species name contains the suffix 'ensis' (and the 'ae' suffix can be used this also) it indicates that the preceding name-portion is the region (description or actual name) where the plant comes from: eg. D. capensis comes from the Cape of Good Hope area of South Africa, and Nepenthes muluensis is found on Mt. Mulu in Sarawak. Small botanical Latin dictionaries are very helpful in puzzling the meaning of plant names.

Cultivar names can be applied to a species plant – Sarracenia leucophylla cv. 'Tarnok' or Nepenthes thorelii cv. 'Aglow Koto'. Growers may use various subspecies, varieties or forms within a single species to produce a new man-made variation. Although the resulting plant is man-made, its derivation is from within a single species and the species epithet remains in its italicised form. The cultivar name portion must be non-italicised.

It is noteworthy to mention here that, in many cases, within this document and usually in verbal intercourse among CPers, that for the monotypic genera, the species names are not used. This is because the genus name is quite adequate to identify the plant, and the species name is considered an unnecessary redundancy. Such usage is not strictly correct, but it is normal practice. This will be noticeable when referring to Cephalotus, Dionaea and Darlingtonia; being frequently-discussed plants. At one of our monthly VCPS meetings the name follicularis was mentioned – there was some dismay and lapse of time before it was realised that Cephalotus was really the plant being referred to.

Incidentally, the plural of genus is 'genera', and both the singular and plural of the word species is 'species'. Just to introduce a bit of confusion; whilst the abbreviation for species is 'sp', the plural of this  abbreviation is 'spp' – hopefully, not to be confused with the subspecies abbreviation 'ssp'.

What do you mean by complex names like - Drosera binata var. multifida f. extrema?

Sometimes a plant does not just fit into the moulds of genus and species. It may be very similar to some species, but different in some subtle yet significant way. If it is not so different as to be a different species, it may be defined as being a different subspecies (like Sarracenia rubra ssp. gulfensis). Other species subcategories exist, such as 'varieties' or 'forms'. For example, some varieties of Drosera binata (binata = fork-leafed) produce leaves with many (multi) branches, hence D. binata var. multifida. A rare form has a great number (more than around 16) leaf tips, and is called D. binata var. multifida f. extrema. All this does not mean you can call plants whatever you like; inventing names along the way. Botanical Latinised names must be published in a scientific journal before they are considered valid.

How do you pronounce the Latinised names?

There are two approaches to this. The first is to be precise and pronounce everything using the correct Latin. The second approach is more relaxed, and operates on the principle that since Latin is a dead language, its pronunciation doesn't really matter. Say it however you feel comfortable. Consider the species of pitcher plant found in mountainous terrain, Sarracenia oreophila. Some people pronounce this orry-AH-fila, others say orr-ee-oh-FIL-a (preferred), and others say orr-ee-oh-FYE-la. Just as long as you get the point across, it does not matter.

To provide some assistance with this, it is recommended, where this is phonetically possible, that every vowel is pronounced as being in a separate syllable. The letter 'Y' is classed as a sixth vowel in this instance, where is creates a distinct 'i' or 'I' sound. Latin names like leucophylla, where 'eu' has a single vowel sound, must be pronounced with that in mind. The only sensible rule to apply is that if it sounds reasonable when you hear it, and you can say it without getting your tongue severely knotted, then that will be okay.

In some books, particularly in the earlier title by Gordon Cheers, there is reference to a fictitious CP species called Sarracenia oreophylla – there is no such plant. It is unfortunate that this erroneous label was associated with the species S. oreophila, in most cases.

The error probably came about because of the phonetic similarity between the latter portions of the species names in S. leucophylla and S. oreophila.

In the leucophylla name, we have from the Greek: leuco (white-) and phylla (-leaf) – a very appropriate description for those pitchers.

The species epithet for Sarracenia oreophila is derived from: Latin oreas or Greek oreias (mountain-) and Greek phila (-loving) – its natural habitat being some isolated mountainous areas in north-eastern Alabama in USA.

What about hybrid plants?

In most of the CP genera, particularly Nepenthes and Sarracenia, many natural and man-made hybrids exist. The scientific names are used in a slightly different way to accommodate the hybrids and the cultivars.

Natural Hybrids.

Presuming, of course, that the usual conventions of the naming system are used in any instance, when an 'X' is placed following the italicised genus epithet, then the plant is a natural hybrid. For instance, Nepenthes X kinabaluensis (a natural hybrid, found on Mt. Kinabalu) or, in the abbreviated form N. X kinabaluensis (verbalised as: "nepenthes hybrid kinabaluensis"). Or, in the sundew genus, Drosera X badgerupii is a natural hybrid, usually found in Western Australia.

 Man-made Hybrids.

When the second part of the plant name is shown as normal upright letters (non-italicised), without an 'x' preceding it and enclosed within single quote marks, this indicates that the plant is a man-made hybrid. Although many of the man-made hybrid names are obviously Latinised, this is not necessary, and in recent times not acceptable. More than one word is permitted in such names (up to a recommended maximum of three), with each word starting with a capital letter. Consider Nepenthes 'Rokko' (verbally – "nepenthes hybrid rokko") or Sarracenia 'Marston Mill' (verbally – "sarracenia hybrid Marston Mill"): both of these are man-made hybrids, the latter plant produced by Adrian Slack.

Cultivars.

Cultivar names can be applied to species or either of the hybrid types, as in Sarracenia X mitchelliana cv. 'Red Lips' or Nepenthes 'Aigae' cv. 'Akaba'. The original name of the parent plant (species, natural hybrid, or man-made hybrid) is retained in its original form, with the cultivar abbreviation and horticultural name appended. The cultivar names must be constructed and obey the same rules as for man-made hybrid names.

Un-named Hybrids.

If a lower-case letter 'x' is placed between a pair of names, the plant is an unnamed hybrid. So, Nepenthes rajah x khasiana (if it ever could exist) should be interpreted and spoken as: "nepenthes rajah crossed with khasiana".

Pre-existing hybrids can also be used similarly: Sarracenia X excellens x 'Judith Hindle', spoken as "sarracenia hybrid excellens crossed with hybrid 'Judith Hindle'". (Sarracenia X excellens is a natural hybrid and S. 'Judith Hindle' is a man-made hybrid.)

Similarly, Sarracenia leucophylla x 'Willisii' ("Sarracenia leucophylla crossed with hybrid willisii"). (Sarracenia 'Willisii' is a man-made hybrid).

An interesting case arises when two natural hybrids are used as parents – Sarracenia X popei x X moorei.

The point to remember is that the plant definitions, when specified in this manner, are totally unambiguous – nobody can say: "Oh, I thought you meant something else."