Part 2: Plant Nomenclature - The Botanical Names of Species

The common names of plants quite often describe their unique structures, such as the inflorescence of Heliconia rostata which appears like Lobster's Claw for which it is popularly known.   

 Heliconia rostata a tropical ornamental plant which appears like  the claws of a lobster's Claw, for which it is commonly called Lobster's Claw.
By convention, botanical names of species are binomials, that is they are composed of two words in Latin form. The first word is a singular noun and is the name of the genus or the generic name to which the plant is assigned. The second word is an adjective modifying the generic name and must agree in gender with the latter. This word is the specific epihet. It is a noun in apposition, or a possessive noun.

Examples of the combination are Coffea arabica, Cyperus papyrus, and Dendrobium densiflorum. This  binary nomenclature  is the scientific way of referring to a specimen so everyone knows what one is talking about. It was so convenient that very soon it was universally adopted. It is from Carolus Linnaeus’ Species Plantarum, 1753, that we derive our modern system of naming plants. Linnaeus named thousands of species of plants and animals based on specimens that were sent to him from collectors all over the world.

A genus (referred to in the plural as genera) may comprise a single species or several hundred species. A species (always in the singular form) is distinguishable from other species in the same genus by species – specific characteristics. As an example, the white mulberry is known as Morus alba and the black mulberry as Morus nigra, respectively. They are thus, in the Morus genus and are known by the species names alba and nigra, respectively. The genus Morus is in the family Moraceae (fig family), along with such common plants as Ficus, Artocarpus, and Streblus. The family name, however, is not included in the binomial.

The Genus/Generic name

      Often genus names such as the liver-like leaves of Hepatica, gave generic names to still others which maybe real persons of distinction (e.g., Allamanda, Begonia, Bougainvillea, Guzmania, Cattleya, and Nicotiana) or mythical persons (e.g., Amaryllis, Artemisia, Dianthus, Iris, Liriope, and Narcissus. Sometimes they are Latin names (Asparagus, Ficus, Raphanus, Rosa, Vitis), or names directly from Greek (Caryota, Cassia, Cestrum, Nerium, Pistia).

     Information about a plant is sometimes expressed in a generic name because it indicates in a general way the kind of plant under consideration. With familiar genera we can recognize the plants by their generic names, for example, Rosa, as rose and Pinus as a pine, both of which are ancient colloquial names. Latin inflectional endings are used for both generic and specific epithets.

      After a generic name has been spelled out at least once, it may be abbreviated by using the initial capital letter, for example, C. for Capsicum. Generic names may not consist of two words unless they are joined with a hyphen.

      The genus refers to a group of plants, which share a certain structural characteristics that are permanent, and largely confined to that group. Hibiscus, for example, is a Greek name for mallow. Some 220 species of annuals, perennials, sub-shrubs, shrubs, and trees belong to this genus that occurs in warm temperate and tropical regions. Of these, about 10 species are occurring in the Philippines. Most of them are cultivated for their big, showy and distinctive flowers having five petals that are united at the base and a projecting column of stamens and style. A genus is therefore a group of plants, which have been given the same first name.

The Species Name/Specific Epithet

      The specific epithet sets one species apart from another within the genus. A species has been defined as a group of interbreeding natural populations, which are genetically isolated from other such groups or populations, that is, it cannot create fertile hybrids. This species concept, which is biological one, is the basis of naming species.

    

     Any specific epithet is given, as long as it uses the Latin rules of grammar. The names are chosen by the first scientist to identify a new plant species. Sometimes, the epithet is merely descriptive, indicating a distinguishing characteristic of structure or flower color in the species. For example, the epithet serrata is an adjective, meaning saw-toothed; the epithet hirtifolia means hairy leaved, and barbiflora, bearded flower. The term alba or albus is the Latin for white and is a common species name in many genera.

     But some species names are much more fanciful than mere description. They may refer to a place where the species is native or where the species was first discovered. The species name samarensis means “from Samar” and littoralis indicates that the species is “of the shore”.  It may honor a person, santosii, for example, may refer to Mr. Santos, the person credited with the collection or discovery of the species.

     There are thousands of specific epithets. Some are used only once, but a number of them have been applied to other plants such as  chinensis, sativa, esclentum, officinalis, vulgaris, and hirsuta. Some have prefixes, suffices, and different endings depending upon other criteria. A knowledge of the meaning of specific epithets aids in remembering botanical names.

Author Citation

One or more authorities often follow the specific epithet. This refers to the name (or names) of person (or persons) who first described the species. The author’s names are abbreviated unless they are very short. The botanical name, including authority (Linnaeus) for the Arabian coffee plant is Coffea arabica L (PHOTO). Other examples include Adiantum tenerum Swartz, (maidenhair fern), Dracaena marginata Lam. (red-margined dracaena) and Agathis philippinensis Warb. (almaciga).

Coffea arabica, also known as the Arabian coffee, "coffee shrub of Arabia", "mountain coffee", or "arabica coffee", is a species of Coffea. It is believed to be the first species of coffee to be cultivated, and is the dominant cultivar, representing some 60% of global production. 

Sometimes authority names are separated by the prepositions ex or in.  Names separated by ex means that the second author published a name proposed , but never published by the first, while the word in means that the first author published the species in a book or article edited or written in part by the second author. Examples include Gossypium tomentosum Nutt. ex Seem., which may be shortened to G. tomentosum Seem., and Viburnum ternatum Rehder in Sargent, which should be shortened to V. ternatum Rehder.

Why do botanical names get changed?

From time to time, botanical names are changed. Increased knowledge concerning a species’ phylogenetic relationship often leads to the transfer of one species to another genus to which the plant is found to belong correctly. As a result, a new name combination is made. According to the International Rule of Priority the earliest specific epithet, published in accordance with the rules, must be retained, unless by so doing the author is duplicating an existing name under the new genus. Geranium zonale L. (1753), upon being transferred to the genus Pelargonium, becomes Pelargonium zonale (L.) Ait. (1789). The original author’s name is retained in brackets before that of the author of the new combination.  The abbreviations - L. and  Ait. - stand for the names of Linnaeus and Aiton, respectively, authors of the above  botanical names.

    

If it turns out that a botanical name was mistakenly given to more than one plant, a correction must be made. One cannot give the same name for one plant species. The first name published is the accepted one (Rule of Priority), and any other names that may have been used incorrectly are now called synonyms. These are “unavailable” names that cannot be used. We often list botanical synonyms because not everyone knows when a plant has been corrected.

Botanical Names below the Species

Carl Linnaeus, also known after his ennoblement as Carl von Linné, was a Swedish botanist, physician, and zoologist who formalized binomial nomenclature, the modern system of naming organisms. He is known as the "father of modern taxonomy".

A plant species may be further classified according to the subspecies or variety. Geographic races are often treated at the sub-specific or varietal level, and in these cases sub-specific or varietal epithets are provided. Formal subspecies and variety names are chosen according to the same rules as species names and are also italicized. Often they are preceded by an abbreviation such as ‘subsp.” or “var.” to include their relationship to the species.

Examples are Philodendron scandens C. Koch  & H. Sello subsp. oxycardum (Schott.) Bunt.; Pterocarpus indicus Willd.  subsp. indicus (Willd.) Rojo; Aglaonema commutatum Schott. var. elegans (Engl.) Nichols; Phoenix hanceana Naud. var. philippinensis Becc. The epithet of the variety or subspecies that contains the type specimen of the species repeats that of the species, this variety is often called nominate or “typical”.

Horticultural Names
 Plants, which have usually arisen as the result of deliberate crossing and selection, are properly termed “cultivars” to distinguish them from natural or wild varieties. They comprise an assemblage of cultivated plants that is clearly distinguished by any characters (morphological, physiological, cytological, chemical or others), and that following reproduction (sexual or asexual) retains its distinguishing character. If a new type of tomato were developed by cross pollination in a breeding program, it would be a cultivar.

Cultivar is derived from the terms cultivated variety. A cultivar name is not Latinized; it is written with a capital initial letter. It is either preceded by the abbreviation “cv” (cultivar) or often set out in single quotes. Cultivar names may be used after generic, specific or common names. Examples of some cultivars are Hosta Decorata; Citrullus cv. Crimson Sweet; Allamanda cathartica L. Hendersonii and Aglaonema simplex Bl. Angustifolium.

     

Cultivars should not be confused with botanical varieties, which usually represent naturally occurring geographic races or morphologically distinct populations that are well adapted to particular ecological conditions.

Names of Hybrids

Hybrids, which result from the interbreeding of separate species and occasionally, species from separate genera, or were created by humans through cross-pollination of separate species, have special designations. A multiplication sign (x) is used in the botanical name to indicate that the genus or species is the result of a hybrid cross. In Rhododendron (repens x didymum) Carmen, the cultivar’s named Carmen is shown to have been raised from a cross between two species of Rhododendron; R. repens and R. didymium

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Valid and Effective Publication of Botanical Names

Under the Code of Botanical Nomenclature, a botanical name will have no standing unless validly published with a technical description of the plant including scientific illustrations, Latin diagnosis and indication of type specimens and where they are deposited. It should be published in a recognized scientific journal and made available to scientific libraries. Botanical names are standardized and agreed upon throughout the world. 

Botanical names sound strangely formal and scientific. But, a valuable product of the formality of botanical naming science is that, when you identify a plant by its botanical name, you can be sure that there is one and only one plant by that name.

Botanical Names Pronunciation

There is no universal system for pronouncing botanic names. Unlike the use of botanical names, their pronunciation is not governed by rules. The majority of people, therefore, pronounce them in any way they like or treat them as if they are in their own language. Most English-speaking botanists and horticulturists use the traditional English pronunciation. Most letters of the alphabet are pronounced in the same as in English. Every vowel or diphthong is pronounced, and there are no silent letters at the end of a word. However, when a word begins with cn, gn, or pt, the first letter is silent. British scientists, however, would have different pronunciation of names from most Americans. Most European way of pronouncing Latin names approximate those of the educated Romans. The Latin American scientists have also their own, quite different from those of the traditional English method. ~