Autonyms in Botanical Nomenclature: Rules and Applications
In the precise world of botanical nomenclature, names are not merely labels; they are governed by strict regulatory frameworks. One of the most unique mechanisms within the International Code of Nomenclature for algae, fungi, and plants (ICN) is the creation of autonyms. These are names that are established automatically when a taxon is subdivided, ensuring that the original type of a genus or species remains correctly identified within its new groupings.
An autonym is a name that "repeats unaltered" the genus name or the species epithet of the taxon being subdivided. Because they are created by the very act of subdivision, they may not even be explicitly mentioned in the original scientific publication that triggered their creation.
Key Facts
- Automatic Creation: Autonyms are established automatically under the ICN when a legitimate genus or species is subdivided.
- No Author Citation: Because they are created by rule rather than by a specific author's description, autonyms are cited without an author.
- Nomenclatural Priority: Autonyms hold priority over other names of the same rank established at the same time.
- Unaltered Epithets: An autonym must repeat the generic or specific name exactly; any variation renders the name invalidly published.
- Shared Type: The nomenclatural type of an autonym is identical to the type of the genus or species from which it is derived.
How Autonyms are Established
The establishment of autonyms is governed by specific articles within the ICN, primarily Articles 6.8, 22, and 26. The process depends on whether the subdivision occurs at the generic level or the infraspecific level.
Infrageneric Autonyms
When a genus is divided into smaller subdivisions—such as subgenera, sections, or series—an autonym is created for the group that contains the original type of the genus. This subdivision is known as an infrageneric taxon. To be valid, the epithet of this subdivision must repeat the generic name unaltered. For example, if a botanist publishes a new subgenus within the genus Rubus, the subdivision containing the type of Rubus automatically becomes Rubus subgen. Rubus.
Infraspecific Autonyms
Similarly, when a species is divided into infraspecific taxa (such as varieties or subspecies), an autonym is automatically established for the taxon that includes the type of the species. In this case, the final epithet must repeat the specific epithet unaltered. For instance, if new varieties are described within the species Elmerrillia papuana, the variety that contains the original type automatically becomes Elmerrillia papuana var. papuana.
Rules of Interpretation and Priority
The application of these names is determined by nomenclatural types, which are preserved specimens or illustrations. When a botanist describes a new taxon, any remaining elements of the original species that are not included in the new taxon automatically form a new infraspecific taxon—the autonym.
A critical aspect of autonyms is their priority. Under Article 11.6, an autonym is considered to have been published at the exact same time as the names that established the other subdivisions. If a conflict arises during taxonomic reclassification, the autonym takes precedence. For example, if a subspecies is moved into a different species, the autonymic name maintains priority over other competing names of the same rank.
| Feature | Infrageneric Autonym | Infraspecific Autonym |
|---|---|---|
| Rank Level | Below Genus (e.g., Subgenus, Section) | Below Species (e.g., Variety, Subspecies) |
| Epithet Requirement | Repeats the Generic name unaltered | Repeats the Specific epithet unaltered |
| Author Citation | None | None |
| Type Source | The Genus type | The Species type |
Frequently Asked Questions
What happens if a subdivision name does not repeat the genus name exactly?
If a subdivision is intended to include the type of the genus but its epithet does not repeat the generic name unaltered, that name is not considered validly published. The autonym, however, remains validly published by default.
Are autonyms always mentioned in scientific papers?
No. An autonym is created as a side-effect of the valid publication of other subdivisions. It may exist and be validly published even if it does not appear in print in the original publication.
Can an autonym be created if the genus name is illegitimate?
No. Autonyms are only established if the name of the genus or species being subdivided is legitimate.
Why do autonyms not have an author listed after them?
Autonyms are established automatically by the rules of the ICN rather than being formally described by a specific individual. Therefore, they do not receive an author citation.
Does an autonym have priority over other names?
Yes. According to Article 11.6, the autonym has nomenclatural priority over the names that established the other subdivisions at the same rank and time.