Validity synonymy and homonymy

As I have explained earlier, a taxon name must fulfill a set of conditions to be available in terms of Code compliance. Among the available names, only the oldest available name is what systematists call valid and has priority over the younger names. The valid name of a taxon is sometimes referred to as the correct name, which means that open nomenclatural problems have been solved and that a single name retained, that under the provisions of the Code, is the only approved one. The date of publication of the original description of a name is thus of crucial importance and must be carefully determined. It must be emphasized that the principle of priority applies to the species, genus, and family levels only but not to levels above the family rank.

In by far the most cases the valid name is the oldest name. Exceptions occur when the oldest name, in case of a species, is already in use in the genus, resulting in homonymy. Then the younger of the homonymous names would no longer be valid but must be replaced by the next available name of the same species, if any exists. An example is a subspecies of the common Chimpanzee, Pan troglodytes verus Schwarz, 1934 (originally described as a subspecies of Pan satyrus Linnaeus, 1758, the species name of which was suppressed by the International Commission on Zoological Nomenclature in 1999). The oldest available name of this subspecies is Simia chimpanse Matschie, 1904, but, despite having priority due to the early publication date, Matschie's name cannot be used because it is a junior homonym of another species, Satyrus chimpanse Mayer, 1856. Since Satyrus chimpanse Mayer is considered to be identical to, that is, a synonym of, the nominate subspecies, Pan troglodytes troglodytes, the species group name chim-panse occurs twice within Pan, by Matschie, 1904, and by Mayer, 1856, respectively. This is called secondary homonymy, since the two names under discussion were first proposed in different genera and got in conflict after being considered to belong in the same genus. Simia chimpanse Matschie was published half a century later than Satyrus chimpanse Mayer, and thus as the younger of the two names must be replaced. The next available name is Pan satyrus verus Schwarz, published in 1934, which then becomes valid. In many species, however, no name is available other than the originally proposed name. Then the revising author has the authority to propose a replacement name, which then becomes available with the reviser as the correct author and the date of his publication.

If a single taxon is given two or more names, each of these names is a synonym. The earliest published synonym is referred to as the senior synonym, even if it is considered to be the valid name. Any other earlier names of the same taxon are called junior synonyms. In most cases in practical taxonomy, systema-tists are confronted with the question if two independently published species names that were based on different name-bearing types actually represent the same species. This kind of synonymy with different types is called subjective synonymy because it expresses the scientific conviction of the revising author that the two names refer to the same thing. Names applied to a species on the basis of the same type specimens are objective synonyms.

0 0

Post a comment