Product Code Database
In taxonomy, the scientific classification of living organisms, a synonym is an alternative scientific name for the accepted scientific name of a taxon. The botanical and zoological codes of nomenclature treat the concept of synonymy differently.
Unlike in other contexts, in taxonomy a synonym is not interchangeable with the name of which it is a synonym. In taxonomy, synonyms are not equals, but have a different status. For any taxon with a particular circumscription, position, and rank, only one scientific name is considered to be the correct one at any given time (this correct name is to be determined by applying the relevant code of nomenclature). A synonym cannot exist in isolation: it is always an alternative to a different scientific name. Given that the correct name of a taxon depends on the taxonomic viewpoint used (resulting in a particular circumscription, position and rank) a name that is one taxonomist's synonym may be another taxonomist's correct name (and vice versa).
Synonyms may arise whenever the same taxon is described and named more than once independently. They may also arise when existing taxa are changed, as when two taxa are joined to become one, a species is moved to a different genus, a variety is moved to a different species, etc. Synonyms also come about when the codes of nomenclature change, so that older names are no longer acceptable; for example, Erica herbacea Carl Linnaeus has been rejected in favour of the conserved name of Erica carnea L. and is thus its synonym. ICN, Appendix IV
Changes of scientific name have two causes: they may be taxonomic or nomenclatural. A name change may be caused by changes in the circumscription, position or rank of a taxon, representing a change in taxonomic, scientific insight (as would be the case for the fruit fly, mentioned above). A name change may be due to purely nomenclatural reasons, that is, based on the rules of nomenclature; as for example when an older name is (re)discovered which has priority over the current name. Speaking in general, name changes for nomenclatural reasons have become less frequent over time as the rules of nomenclature allow for names to be conserved, so as to promote stability of scientific names.
One basic principle of zoological nomenclature is that the earliest correctly published (and thus available name) name, the senior synonym, by default takes precedence in naming rights and therefore, unless other restrictions interfere, must be used for the taxon. However, junior synonyms are still important to document, because if the earliest name cannot be used (for example, because the same spelling had previously been used for a name established for another taxon), then the next available junior synonym must be used for the taxon. For other purposes, if a researcher is interested in consulting or compiling all currently known information regarding a taxon, some of this (including species descriptions, distribution, ecology and more) may well have been published under names now regarded as outdated (i.e., synonyms) and so it is again useful to know a list of historic synonyms which may have been used for a given current (valid) taxon name.
Objective synonyms refer to taxa with the same type and same rank (more or less the same taxon, although circumscription may vary, even widely). This may be species-group taxa of the same rank with the same type specimen, genus-group taxa of the same rank with the same type species or if their type species are themselves objective synonyms, of family-group taxa with the same type genus, etc. ICZN, Art. 61.3
In the case of subjective synonyms, there is no such shared type, so the synonymy is open to taxonomic judgement, ICZN, Art. 61.3.1 meaning that there is room for debate: one researcher might consider the two (or more) types to refer to one and the same taxon, another might consider them to belong to different taxa. For example, John Edward Gray published the name Antilocapra anteflexa in 1855 for a species of pronghorn, based on a pair of horns. However, it is now commonly accepted that his specimen was an unusual individual of the species Antilocapra americana published by George Ord in 1815. Ord's name thus takes precedence, with Antilocapra anteflexa being a junior subjective synonym.
Objective synonyms are common at the rank of genera, because for various reasons two genera may contain the same type species; these are objective synonyms. ICZN, Art. 61.3.3 In many cases researchers established new generic names because they thought this was necessary or did not know that others had previously established another genus for the same group of species. An example is the genus Pomatia Beck, 1837,p. 43 in Beck, H. 1837. Index molluscorum præsentis ævi musei principis augustissimi Christiani Frederici. – pp. 1–100 1837, 101–124 1838. Hafniæ. which was established for a group of terrestrial snails containing as its type species the Burgundy or Roman snail Helix pomatia—since Helix pomatia was already the type species for the genus Helix Linnaeus, 1758, the genus Pomatia was an objective synonym (and useless). On the same occasion, Helix is also a synonym of Pomatia, but it is older and so it has precedence.
At the species level, subjective synonyms are common because of an unexpectedly large range of variation in a species, or simple ignorance about an earlier description, may lead a biologist to describe a newly discovered specimen as a new species. A common reason for objective synonyms at this level is the creation of a replacement name.
A junior synonym can be given precedence over a senior synonym, ICZN, Art. 23.9 "reversal of precedence" primarily when the senior name has not been used since 1899, and the junior name is in common use. The older name may be declared to be a nomen oblitum, and the junior name declared a Nomen oblitum. This rule exists primarily to prevent the confusion that would result if a well-known name, with a large accompanying body of literature, were to be replaced by a completely unfamiliar name. An example is the European land snail Petasina edentula (Draparnaud, 1805). In 2002, researchers found that an older name Helix depilata Draparnaud, 1801 referred to the same species, but this name had never been used after 1899 and was fixed as a nomen oblitum under this rule by Falkner et al. 2002.Falkner, G., Ripken, T. E. J. & Falkner, M. 2002. Mollusques continentaux de France. Liste de référence annotée et bibliographie. – pp. 1–2, 1–350, 1–3. Paris.
Such a reversal of precedence is also possible if the senior synonym was established after 1900, but only if the International Commission on Zoological Nomenclature (ICZN) approves an application. (Here the C in ICZN stands for Commission, not Code as it does at the beginning of § Zoology. The two are related, with only one word difference between their names.) For example, the scientific name of the red imported fire ant, Solenopsis invicta was published by Buren in 1972, who did not know that this species was first named Solenopsis saevissima wagneri by Santschi in 1916; as there were thousands of publications using the name invicta before anyone discovered the synonymy, the ICZN, in 2001, ruled that invicta would be given precedence over wagneri.
To qualify as a synonym in zoology, a name must be properly published in accordance with the rules. Manuscript names and names that were mentioned without any description ( Nomen nudum) are not considered as synonyms in zoological nomenclature.
In botany, although a synonym must be a formally accepted scientific name (a validly published name): a listing of "synonyms", a "synonymy", often contains designations that for some reason did not make it as a formal name, such as manuscript names, or even misidentifications (although it is now the usual practice to list misidentifications separately ICN, Recommendation 50D).
The status of a synonym may be indicated by symbols, as for instance in a system proposed for use in paleontology by Rudolf Richter. In that system a v before the year would indicate that the authors have inspected the original material; a . that they take on the responsibility for the act of synonymizing the taxa.
The accurate use of scientific names, including synonyms, is crucial in Medical research and pharmacology research involving plants. Failure to use correct botanical nomenclature can lead to ambiguity, hinder reproducibility of results, and potentially cause errors in medicine. Best practices for publication suggest that researchers should provide the currently accepted binomial with author citation, relevant synonyms, and the accepted family name according to the Angiosperm Phylogeny Group III classification. This practice ensures clear communication, allows proper linking of research to existing literature, and provides insight into phylogenetic relationships that may be relevant to shared chemical constituents or physiological effects. Online databases now make it easy for researchers to access correct nomenclature and synonymy information for plant species.
|
|
