Principle of priority

1. The first formal scientific name published for a plant or animal
   correct name in botany (principle of synonymy
   ).
2. Once a name has been used, no subsequent publication of that name for another taxon shall be valid (zoology) or
   validly published (botany) (principle of homonymy
   ).

Note that nomenclature for botany and zoology is independent, and the rules of priority regarding homonyms operate within each discipline but not between them. Thus, an animal and a plant can bear the same name, which is then called a hemihomonym.

There are formal provisions for making exceptions to the principle of priority under each of the Codes. If an archaic or obscure prior name is discovered for an established taxon, the current name can be declared a

History

The principle of priority has not always been in place. When

During the 19th century, the principle gradually came to be accepted by almost all botanists, but debate continued to rage over the conditions under which the principle might be ignored. Botanists on one side of the debate argued that priority should be universal and without exception. This would have meant a one-off major disruption as countless names in current usage were overturned in favour of archaic prior names. In 1891, Otto Kuntze, one of the most vocal proponents of this position, did just that, publishing over 30000 new combinations in his Revisio Generum Plantarum.^[3] He then followed with further such publications in 1893, 1898 and 1903.^[3] His efforts, however, were so disruptive that they appear to have benefited his opponents. By the 1900s, the need for a mechanism for the conservation of names was widely accepted, and details of such a mechanism were under discussion. The current system of "modified priority" was essentially put in place at the Cambridge Congress of 1930.^[3]

In zoology

The Principle of Priority is one of the guiding principles of the

In botany and horticulture, the principle of priority applies to names at the rank of family and below.^[5][6] When moves are made to another genus or from one species to another, the "final epithet" of the name is combined with the new genus name, with any adjustments necessary for Latin grammar, for example:

• When Festuca subgenus Schedonorus was moved to the genus Lolium, its name became Lolium subgenus Schedonorus.^[7]
• Xiphion danfordiae Baker was moved to Juno danfordiae (Baker) Klatt, Iridodictyum danfordiae (Baker) Nothdurft^[8] and Iris danfordiae (Baker) Boiss.^[9] The name enclosed in parentheses cites the author who published the specific epithet, and the name after the parentheses cites the author who published the new combination of the specific epithet with the generic name.^[10]
• Orthocarpus castillejoides var. humboldtiensis D.D. Keck was moved to Castilleja ambigua var. humboldtiensis (D.D. Keck) J.M. Egger.^[11]
• When Caladenia alata was moved to the genus Petalochilus, the grammatical gender of the Latin words required a change in ending of the species epithet to the masculine form, Petalochilus alatus.^[12]

In zoology, the principle of priority applies to names between the rank of superfamily and subspecies (not to varieties, which are below the rank of subspecies).^[13] Also unlike in botany, the authorship of new combinations is not tracked, and only the original authority is ever cited. Example:

• A.A. Girault published a description of a wasp, as Epentastichus fuscus, on 10 December 1913, and on 29 December 1913, he published a description of a related species, as Neomphaloides fusca.^[14] Eventually, both of these species were later transferred to the same genus, Aprostocetus, at which point they both would have become Aprostocetus fuscus (Girault, 1913), except that the one published 19 days later was the junior homonym, and its name was replaced with Aprostocetus fuscosus Bouček, 1988.^[15]

See also

• Kew Rule

References