READINGS
- Textbook by Judd et al., 3rd edition, Appendix 1, pages 543 – 552.
- Textbook by Judd et al., 2nd edition, Appendix 1, pages 511 – 520.
- Download a reading by Dr. Robertson as a pdf file.
no-men-clature
Your first take-home lecture assignment, worth up to 2% of your final grade, is due in class Friday, February 1. This assignment will be distributed in lecture or you may print out a copy of this assignment at this link. Be sure to include your name and laboratory section (AB2 or AB3), and also remember to underline Latin names. Penalties will be assessed for assignments handed in late (i.e., after class); assignments more than 24 hours late will not be graded. Answers will be posted (on the web) immediately after lecture that day. Graded assignments will be returned in lab.
This is the version with IMAGES, which takes longer to load! For the TEXT version without images, click here.
WHAT YOU NEED TO KNOW ABOUT NOMENCLATURE
- Pronunciation — no silent “e” at end of word
- Binomial system of naming species developed by Linnaeus, which consists of the name of the genus, the specific epithet, and the authority.
- Capitalize name of genus
- The specific epithet is always correct in lower case.
- The name of the genus and the specific epithet should always be underlined or placed in italics. [but not the authority]
- The three subspecific ranks for plants, and how they differ. Why the abbreviation of the rank must always be used (that is, why trinomials are incorrect). The subspecific epithet must also be underlined or placed in italics.
- How to indicate the name of an interspecific hybrid — two ways. [Remember not to underline/italicize the "×"]
- Names of cultivated plants, new names in a modern language, rank of cultivar, name capitalized, NOT italicized but rather placed either in single quotation marks or preceded by the abbreviation cv.
- Four of the six principles of botanical nomenclature, especially
- botanical nomenclature independent from zoological nomenclature
- rule of priority of publication, which begins with Linnaeus Species Plantarum, 1 May 1753
- each group can have only one correct name and the correct name of a species is the combination of the earliest generic name with the earliest specific epithet
- names of plants are treated as Latin.
TWO TYPES OF NAMES FOR PLANTS:
- common names — in a modern language, used in everyday conversation (some also made up for use in field guides)
- scientific names — in Latin or Latinized form, used for scientific purposes
COMMON NAMES
- In the language of the country or region. All of these common names refer to beech trees — beech (English); hêtre (French); haya (Spanish); faia (Portuguese); Buche (German).
- Use familiar words
- The names by which most people know plants
- Can be stable within a region
- But same common name can be used for more than one plant in different regions
Common names are not standardized for plants — the same name can refer to more than one species
- “Mayflower” could be Maianthemum canadense or Epigaea repens
- 
- “Corn” in the United States is Zea mays, but in Europe “corn”
refers to any kind of grain while Zea mays is called “maize”
- 
The same plant can also have different common names:
- Hedge apple, Osage orange, bowwood, bois -d’arc all are used for Maclura pomifera
Common names can indicate that plants are related
- White oak = Quercus alba, a true oak, as is
- Bur oak = Quercus macrocarpa
But common names can also be misleading
- Poison-oak = Rhus toxicodendron or Rhus diversilobum, relatives of poison ivy, not related at all to oaks
Notice how many common names have two names, white oak, bur oak.
CODE OF NOMENCLATURE
The naming of plants is covered by the International Code of Botanical Nomenclature, a new edition is published after each International Botanical Congress; the current code is the “St. Louis Code,” published in 2000. The following is in the preamble to the Code — “Botany requires a precise and simple system of nomenclature used by botanists in all countries…The purpose of giving a name to a taxonomic group is not to indicate its characters or history but to supply a means of referring to it and to indicate its taxonomic rank.” [You saw the latter in the lecture on the Taxonomic Hierarchy]
The Principles of Botanical Nomenclature
- Botanical nomenclature is independent of zoological nomenclature
- The nomenclature of a taxonomic group is based upon priority of publication
Priority begins with the publication of Linnaeus' Species Plantarum, published 1 May 1753.
- Each taxonomic group with a particular circumscription, position, and rank can bear only one correct name, the earliest that is in accordance with the Rules, except in specified cases.
- Scientific names of taxonomic groups are treated as Latin regardless of their derivation
We are NOT emphasizing the following principles this year.
- The application of names of taxonomic groups is determined by means of nomenclatural types
- The Rules of nomenclature are retroactive unless expressly limited
- To avoid the disadvantages of a strict application of priority, the International Botanical Congresses have authorized the CONSERVATION of widely used family, generic, and (at the last two Congresses) species names, even though these names are NOT the oldest names.
SCIENTIFIC NAMES
PRONUNCIATION OF BOTANICAL NAMES
Names of genera identical to English common name
- Chrysanthemum
- Geranium
- Rhododendron
- Magnolia
- Aster
- Catalpa
- Phlox
- Iris
Names of genera similar to English common name
- Lilium — Lily
- Rosa — Rose
- Ulmus — Elm
- Populus — Poplar
However, the names of many genera unfamiliar
Guide to pronunciation of a few genera
- Liatris — li-a'-tris
- Ribes — ri'-bes
- Actaea — ac-te'-a
- Acer — a'-cer
- Eleusine — el- oo'-si-ne
- Glycine — gli-cee'-nee
- Androsace — an-dro'-sa-ce
- Aloë — al-o'-e; pronounced al'-o in English
- Protea — pro-te'-a; pronounced pro'-te-a in English
- Desmanthus illinoensis
- des-man'-thus
- il-i-no-en'-sis
MEANINGS OF LATIN NAMES
GENERA
- Bauhinia — two brothers
- Commelina — three brothers
- Tillandsia — Tillands “by land” Map
- 
- Clarkia — for William Clark
- Lewisia — for Meriwether Lewis
- Andromeda, Cassandra, Cassiope, Leucothoë, Phyllodoce, Pieris — Greek mythology
- Harrimanella — Edward Harriman, railroad tycoon
- Theobroma — Food of the Gods
- Cornus — ancient name, also a horn
- Echinacea — hedgehog or sea urchin
- 
SPECIFIC EPITHETS
- Rosa carolina — from Carolina ( Carolina was a big area back then)
- Maianthemum canadense — from Canada
- Acer japonicum — from Japan
- Acacia melanoxylon — black wood
- Acer carpinifolium — leaves like Carpinus
- Acer palmatum — palmately lobed leaves
- Acer rubrum — red
- Acer saccharum — sugar
See textbook by Judd et al., Appendix 1, pages 512–513 for more meanings of Latin names.
SCIENTIFIC NAMES OF SPECIES
The scientific names of species were originally descriptive phrase polynomials, such as Rosa carolina fragrans, foliis medio tenus serratis. These names were long and difficult to remember.
In 1753, Linnaeus first consistently used binomial names for plants. This system still used today. The idea of two words as names is also common in English, as white oak.
The BINOMIAL SYSTEM is used for the names of species. The SCIENTIFIC NAME of a species is the combination of the name of the genus with the specific epithet. To be complete, the scientific name includes the AUTHORITY or person who described the species.
| Genus |
Specific epithet |
Authority |
| Rosa |
carolina |
Linnaeus |
| Quercus |
velutina |
Lamarck |
- The plural of genus is GENERA.
- The word SPECIES is both singular and plural.
- The name of the genus and the specific epithet are EITHER underlined or italicized.
- The name of a genus is always capitalized. The names of genera are treated as NOUNS.
- It is always correct to write the specific epithet in all lower case [Species named after people and after old generic names may be capitalized, i.e., Quercus Shumardii, Lindera Benzoin].
- The specific epithet is usually considered to be an adjective that modifies the genus (noun), and it agrees in gender with the genus. Rosa rubrifolia, Rubus odoratus, Quercus alba
We are NOT emphasizing the following points this year.
When several species of one genus are given in sequence, the name of the genus can be abbreviated to its first letter. Crataegus phaenopyrum, C. mollis, C. pruinosa, C. viridis
The authority can be abbreviated to save space, especially for authors who described a large number of species. The author’s name is never italicized or underlined. Crataegus viridis Linnaeus, Crataegus viridis L.
There may be joint authors, such as: Crataegus berberifolia Torrey & Gray. These may also be abbreviated, i.e., C . berberifolia T. & G. There are standardized lists of author abbreviations.
When a genus, species, or subspecies is described at one rank and then transferred to another rank, the original author is placed in parentheses followed by the author who made the transfer. Rosa carolina var. villosa (Best) Rehder
SUBSPECIFIC RANKS
The Code of Nomenclature recognizes the following SUBSPECIFIC RANKS as part of the taxonomic hierarchy: subspecies, variety, form. Not all species have subspecific taxa. It is permissible to use a lower subspecific rank without a higher subspecific rank.
Species
Subspecies (subsp.) — a geographical race
Variety (var.) — a local or ecological race
Form (f.) — a minor genetic variant that is mixed with other variants
The names of SUBSPECIFIC RANKS consist of the name of the species followed by an abbreviation of the rank, the subspecific epithet, and the authority for the subspecific name.
Phlox pilosa (map)
Phlox pilosa subsp. pilosa
Phlox pilosa subsp. sangamonensis (map)
- 
Prunus lusitanica
Prunus lusitanica subsp. hixa
- 
Spiraea latifolia
Spiraea latifolia var. septentrionalis
- 
Rhus aromatica
Rhus aromatica var. arenaria
Echinacea pallida
Echinacea pallida f. albida
Cercis canadensis f. alba
- 
HYBRIDS are indicated with the "×" [multiplication] sign and may be given in two forms:
- Quercus alba × Q . michauxii [give the species involved in the hybrid, in this case white oak crossed with swamp chestnut oak]
- Quercus × beadlei [treat the hybrid as a species and give it a name]
The cultivated strawberry is a hybrid of these species.
- Fragaria virginiana — Wild strawberry of eastern North America
- Fragaria chiloensis — Wild strawberry of western North America and South America.
- 
The hybrid may be written two ways:
- Fragaria virginiana × F. chiloensis
- Fragaria × ananassa
The common Vanhoutte or Bridal Wearth Spirea is a hybrid between two Asian species. The hybrid may be written two ways:
- Spiraea triloba × S. cantoniensis
- Spiraea × vanhouttei
NAMES OF CULTIVATED PLANTS
The name of a cultivated variety is given the rank of CULTIVAR, which have arisen from plants in cultivation.
It MUST be:
- preceded by the letters cv. or included in single quotation marks
- written in plain text, not underlined or italicized
- treated as ‘fancy’ names in a modern language. NEW cultivar names cannot be in Latin and may not be the same as the botanical or common name of a genus.
- CAPITALIZED
The rank of cultivar is NOT in the subspecific hierarchy, but may be used with any taxon from genus downward
Some cultivars are propagated vegetatively, other are F1 hybrids.
- Cercis canadensis ‘Forest Pansy’
- or
- Cercis canadensis cv. Forest Pansy
- Tilia tomentosa ‘Ster£ing’
- or
- Tilia tomentosa cv. Ster£ing
- Liquidambar styraciflua ‘Autumn Enchantment’
- or
- Liquidambar styraciflua cv. Autumn Enchantment
- Pyrus calleryana ‘Bradford’ or
- Pyrus calleryana cv. Bradford
- 
- Malus domestica ‘Red Delicious’, ‘Red Delicious’, and ‘Jonathan’
- or
- Malus domestica cv. Red Delicious, cv. Golden Delicious, and cv. Jonathan
- 
- Sorbus ‘Joseph Rock’
- or
- Sorbus cv. Joseph Rock
- Rosa ‘Peace’
- or
- Rosa cv. Peace
- Fagus sylvatica ‘Pendula’
- or
- Fagus sylvatica cv. Pendula
- Magnolia × soulangeana ‘André LeRoy’
- or
- Magnolia × soulangeana cv. André LeRoy
The development and marketing of new varieties of cultivated plants is a major industry. In order to protect their legal rights to the new plant varieties, both Trademark and Plant Patent names are sometimes are used, and these are different from cultivar names, which have no legal meaning. For instance, a particular rose is known as Rosa 'Radrazz', but it is widely sold by the trademark name of KNOCK OUT. The rose sold as the Rosie O'Donnell rose has the rather nonsensical cultivar name of Rosa 'WEKwinwin'.
The use of Trademarked and Plant Patent names is complicated. For more information, see <http://www.plantdelights.com/Tony/trademark.html> and <http://www.plantpatent.com/articles.html>.
This is from an e-mail sent by a student who took PB260 in 2001.
“It might be a good idea to explain the differences in scientific nomenclature. I know even in herbaceous perennials/annuals, the names I learned have changed like with Chrysanthemum going to Dendranthemum, and Coleus just changed to something else [Solenostemon], as well as Vinca major going to Catharanthus roseus, and the list goes on. So I do feel it would be good for us know the reasons why names are changing.”
Good question! Especially since the Code of Botanical Nomenclature, as noted above, says that “Each taxonomic group with a particular circumscription, position, and rank can bear only one correct name, the earliest that is in accordance with the Rules …” There are several reasons why you see different publications using different scientific names for the same species.
- One reason is that there has been a name change made necessary by the rules of the Code. Often, this means that someone finds a name that was published earlier than the name currently used.
- A second reason is that some groups of plants are more difficult to classify than others, and different authors may classify them differently.
- Another reason is that modern molecular data may indicate that two groups formerly considered related to each other, and thus placed in the same genus or family, may not be related at all; as a result species can be transferred to different genera, and the circumscription of genera and families may be quite different from their traditional delimitation.
ALTERNATIVE FAMILY NAMES
The Code of Botanical Nomenclature says that family names are based on the name of an included genus. However, there are a few traditional family names that MAY still be used as alternatives to those names ending in –aceae. Below are 7 common examples.
- Apiaceae — Umbelliferae — Umbel family
- Arecaceae — Palmae — Palm family
- Asteraceae — Compositae — Sunflower family
- Brassicaceae — Cruciferae — Mustard family
- Fabaceae — Leguminosae — Bean family
- Lamiaceae — Labiatae — Mint family
- Poaceae — Gramineae — Grass family
WHAT IS WRONG WITH THESE NAMES?
Malus baccata mandschurica
Phlox var. amplexicaulis
Gleditsia triacanthos ‘inermis’
Gleditsia Sunburst
Tilia cordata cv. greenspire
Genus: Diomedea
Species: amsterdamensis
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