International Commission on Zoological Nomenclature

Guidelines for Case Preparation

 The ICZN has provided guidelines in the form of templates to aid authors unsure about how to write applications to the Commission for some of the most common nomenclatural problems.

If you do not know which Article of the Code is relevant to your problem, please use the dichotomous key below to determine which template to download.

Key to types of Cases

I am submitting an application to the Commission to resolve a nomenclatural issue. The name is problematic because

1A. of synonymy/homonymy

2A. The name is a homonym

3A. only at the family-group level; the type genera have similar but not identical names (Art. 55.3.1)

3B. with identical spelling

4A. I want to conserve the junior homonym by suppressing the older homonym (Arts. 23.9.3 and 81.2.1)

4B. I want to conserve both primary homonyms for use in their respective groups as they are not congeneric (Art. 23.9.5)

2B. The name is a synonym

3A. I want to reverse the precedence of the two synonyms without suppressing the older name for the purposes of the Principle of Priority (Arts. 23.9.3 and 81.1)

3B. I want to partially/conditionally suppress the older synonym, i.e. for the purposes of the Principle of Priority but not the purposes of the Principle of Homonymy

4A. the synonyms share the same type (objective synonyms; Arts. 23.9.3 and 81.2.2)

4B. the synonyms do not have the same type but are considered as belonging to the same taxon (subjective synonyms; Arts. 23.9.3 and 81.2.3)

1B. its prevailing usage is threatened by its type

2A. A previously overlooked type has been discovered. I want to maintain prevailing usage by setting the overlooked type aside (Art. 70.2)

2B. The existing type is ambiguous or not in accord with existing usage. I want to designate a neotype as

3A. the existing type’s taxonomic identity cannot be determined (Art. 75.5)

3B. the existing type’s taxonomic identity is not in accord with existing usage (Art. 75.6)