The objects of the Code are to promote stability and universality in the scientific names of animals and to ensure that the name of each taxon is unique and distinct. All its provisions and recommendations are subservient to those ends and none restricts the freedom of taxonomic thought or actions.This point is reiterated in Article 52:
52.1. Statement of the Principle of Homonymy. When two or more taxa are distinguished from each other they must not be denoted by the same name.Yet there are numerous cases in zoological nomenclature where this rule is flagrantly ignored. A few:
- "Echinoidea" is the name of a superfamily containing Echinus (a sea urchin genus), but also the name of a class containing that superfamily.
- "Ophiuroidea" is the name of a superfamily containing Ophiura (a brittle star genus), but also the name of a class containing that superfamily.
- "Chelonia" is a genus of turtle, but also used as the name of the order containing all turtles.
- "Pterodactyloidea" is the name of taxon given various ranks (usually suborder) including most short-tailed pterosaurs, but also the name of a superfamily within that taxon.
This is getting to be an actual problem for me, because parts of Names on Nodes rely on the principle that a name only has one meaning under a given authority. When I create a database entry for urn:isbn:0853010064::Pterodactyloidea, is it for a suborder or a superfamily? ICZN rules actually dictate that the superfamily has precedence, since Family Pterodactylidae Meyer 1830 has precedence over Suborder Pterodactyloidea Plieninger 1901. (The ICZN considers the naming of any taxon whose rank is in the family group as implicitly naming taxa for all ranks of the family group; thus, naming Family Pterodactylidae implicitly names Superfamily Pterodactyloidea, Subfamily Pterodactylinae, Tribe Pterodactylini, and Subtribe Pterodactylina.) People who use "Pterodactyloidea" for a suborder, beware! You are violating the rules of the ICZN! (WhooOOOOoo!!)
The situation with "Echinoidea" is even worse. As near as I can tell, Family Echinidae was named by Gray in 1825 (thus implicitly naming Superfamily Echinoidea), but Class Echinoidea was already named by Leske in 1778. And the ICZN mandates that the superfamily including Echinus must be named "Echinoidea" if the family is named "Echinidae". I'm not sure how this is supposed to play out ... does Echinus simply not get a name for its superfamily? Those poor wee urchins....
(And people wonder why I support an alternative nomenclatural code without mandated suffixes for ranks!)
In the case of Chelonia, people are generally using another name ("Testudines") for the order nowadays, but in other cases I've got a real problem, especially if I hope to automatically pull a lot of this data from other databases.