Why name species? Simply by naming objects, we are able to do a number of useful things; from communicating information about them, through comparing and recording them, to more esoteric concepts such as classifying them. Most commonly encountered species have a number of names which fall into two groups; everyday (common) names and scientific (latin) names.
The everyday names that we use for animals, plants and fungi form a rich part of our heritage. Their early origins are often uncertain, being deeply rooted in language development, herbal knowledge and folklore. However a scan through any species list will emphasise their vivid imagery - it is difficult to forget the name of an Orange Tip butterfly or Snakelocks anemone after your first encounter.
All recognised species are given a unique scientific name, based on the binomial classification system pioneered by Linnaeus. Species names have two components: the group (genus) to which the species belongs and specific name (epithet). For example, Quercus alba (White Oak); Quercus is the genus name for oaks, alba (latin for 'white') describes one particular type (species) of oak.
Scientific names are always written according to a strict convention: the genus is capitalised and the specific epithet is lowercase.
Both components must be used when describing species (although genus may be abbreviated to a single letter after first use).
Scientific names are also generally italicised or underlined.
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Scientific names are occasionally updated, for example when new evidence shows that a species does not belong in the genus to which it was originally assigned.
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In such cases the species is given a new (preferred) scientific name; however existing literature will continue to describe the species by its original name - this therefore remains relevant to understanding the complete description of the species.
Some species are highly variable across their range (although not sufficiently so to prevent interbreeding). These characteristics may be recognised as distinct subspecies, varieties or forms (see Glossary for definitions) in which case a third name is appended to the scientific name, sometimes separated from the binomial name by an appropriate abbreviation. Hybrids also occur between species: these are designated by an 'x', generally between the genus and specific epithet.
Subspecies exhibit characteristics that vary from the typical species type, usually due to geographical isolation.
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Varieties also differ significantly from the species type for other reasons, often related to ecology.
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Forms are minor differences in individuals, often in colour.
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Hybrids are crosses between two different species.
The most common type of hybrid (A x B) occurs between two species in the same genus (interspecific hybrids).
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A less common form of hybrid (x A B) occurs from crossing two species in different genera (intergeneric hybrids).
Both types of hybrid may occur naturally or artificially.
Scientific names are generally followed by the name of the person (Author) who originally described the species and the year in which this occurred. If the species has been reclassified into a different genus than it was originally described, the authors name is parenthesised, and the followed by the name of the author describing the revision.
The Author's name is not underlined or italicized. Names of widely known Authors may be abbreviated (eg. L. for Linnaeus).
Sometimes a new species is described and named by two or more independent authors, often in different countries, at around the same time. In such cases the first published name assumes precedence and alternative names are termed synonyms. Several other mechanisms generate synonyms:
Synonyms may resemble each other if the revisions occur within a genus (eg. Narrow-leaved Marsh Orchid: Dactylorhiza traunsteineri, Dactylorhiza lapponica). However if a species is moved to a different genus the degree of resemblance can range from low (eg. Painted Lady: Cynthia cardui, Vanessa cardui) to non-existent (eg. Wood Calamint: Clinopodium menthifolium, Calamintha sylvatica).
A further minor inconvenience associated with synonyms is that the gender of the species epithet must agree with that of the genus to which it belongs.
This may cause spelling to change slightly if a species is moved to a new genus.
eg. (Wild Chamomile)
Synonyms form an important element of scientific names: it is impossible to retrospectively change species names in published literature, so searching for synonyms is often the only possible way to trace early descriptions of a species.
Naming Species - UK Species website