Nomenclature (the assigning of names):

 

There are rules and conventions for choosing and writing names at different taxonomic levels.

The taxonomic levels we will be emphasizing in this class include:

• Family
• Genus
• Species

Family

You will be learning to recognize approximately 24 families of plants in this class by their characteristics.

In writing the name of a family (e.g., Asteraceae), note that

• the family name is capitalized
• a family name ends in "-aceae"
• Usually, the family is named for a genus in it (in this case, the genus Aster)

Genus

A genus name is capitalized and italicized. Example: Rafinesquia

Species 

A species name is a binomial: it includes both the genus name and a "specific epithet".

The full species name includes the authority or author (the standardized abbreviation of the name of the botanist who originally described it), in addition to the binomial.

Example:

The full name of Rafinesquia californica is Rafinesquia californica Nutt.

• The genus is capitalized and italicized
• The specific epithet is italicized, but NOT capitalized
• "Nutt." refers to William Nuttall, the botanist who described the species in the 1800s. The author is not italicized.

(Wikipedia maintains a long list of standardized abbreviations of authors: https://en.wikipedia.org/wiki/List_of_botanists_by_author_abbreviation_(A) )

 In speaking, people generally do not include the authority. They will just say "Rafinesquia californica".

In writing for publication, the authority is included in the name the first time the species is mentioned. After that, it is left off and the genus may be abbreviated to an initial (e.g., R. californica). [Note that if you are writing about both Rafinesquia californica and Rosa californica, you can't abbreviate the genus without causing mass confusion.]

You can never refer to a species by just its specific epithet. Why? Go to the Calflora website (www.calflora.org/search.html). This is a site the compiles information on California plants from many different sources. Search for "californica" in the "plant name" box. How many plants have the specific epithet "californica"? You cannot use "californica" by itself as the species name and expect anyone to know what plant you are talking about.

 

Origins of names

 The binomial (genus and specific epithet) is often referred to as the scientific name or Latin name of a species. Plants also have common names (more on that later). The Latin name is important for communication of scientists from around the world who speak different languages or dialects.

Generic names (Latin or Latinized nouns with first letter capitalized) may be:

• Aboriginal in origin (example: Quercus = oaks)
• Can be named for a person (Herschfeldia for Hirschfeldt)

 Specific epithets are usually adjectives that agree in gender with the generic name. They are not capitalized. Types of specific epithets include:

• Aborginal: Aesculus hippocastanum from the Greek "hippos" for horse (in this case, horse chestnut)
• Descriptive: Acer rubrum - from the Latin "rubra", meaning red in color
• Impression: Lonicera fragrantissima - fragrant
• Resemblance : Cercocarpus betuloides - looks like a beech. ("Betula" is the the genus of beech trees.)
• Ecological: Colinsia verna - from the Latin "vernus" meaning 'of the spring' (it blooms in spring)
• Economic: Lycopersicum esculentum - "esculentum" means edible
• Named after a person:

• Quercus engelmannii (Engelmann oak), named after George Engelmann (physician & botanist)
• Amsinckia eastwoodiae  ( Eastwood's fiddleneck), named for Alice Eastwood, botanical curator for the California Academy of Sciences in the late 1800s and early 1900s

 Michael L. Charters has compiled an excellent online reference for the meaning and origins of California plant names: http://www.calflora.net/botanicalnames/

The process of naming plants

 To name a new plant taxon (a species or subspecies), a researcher must

1. publish a description of it in a scientific journal or other recognized outlet, and
2. designate a "type specimen", which is a preserved specimen that is deposited in a recognized herbarium. This type specimen serves as the primary reference for the new species or subspecies that is being described.

Names must follow the International Code of Nomenclature (formerly, the International Code of Botanical Nomenclature). This code was first established at the 1905 meeting of the International Botanical Congress. Its purpose was to standardize the names of plants. It is revisited and revised every 6 years with recommended changes being published in the journal Taxon.

 A couple of the rules in the International Code of Nomenclature are that:

• Scientific names of taxonomic groups are treated as Latin regardless of their derivation.
• The nomenclature of a taxonomic group is based upon priority of publication. (This means that if two researchers try to name the same group different things, the first name published is the correct name. Also, if a name is accidentally applied to two different groups, the first group published gets to keep the name.)