The following recommendations are not exhaustive, and are supplemented by the Recommendations and Examples appended to relevant Articles of the Code.
Stability of nomenclature
1. Since it is the object of nomenclature to denote each taxon by a name which is unique, unambiguous and universal, an author should not change the prevailing usage of names, or the sense in which they are used, unless this is required for scientific reasons (i.e. the reclassification of taxa); it is of especial importance that a name should not be transferred to a taxon distinct from that to which it is generally applied.
2. If the provisions of the Code appear to require an action which might threaten stability or cause confusion, that action should not be taken before referring the case to the Commission for advice.
Establishment and formation of new names
3. An author, when drawing up the description of a new nominal taxon, should include comparisons with appropriate related taxa in order to assist later identification of the taxon. Name-bearing type material should be illustrated (or a reference given to such illustration). In the case of new species-group names, when the name-bearing types consist of one or more preserved specimens their deposition in a collection cited by name and location is mandatory [Art. 16.4]; wherever possible this collection should be housed in an appropriate institution.
4. An author establishing a new nominal taxon should clearly state the higher (more inclusive) taxa (e.g. family, order, class) to which the taxon is assigned.
5. An author establishing a new genus- or species-group name should state its derivation (etymology), and in the case of a genus-group name its gender (which should also be clear from the form of the name itself). New names should be in Latin form; they should be euphonious and easily memorable, and should not be liable to confusion with those of other taxa of any rank, or with vernacular words. In the case of genus-group names they should not be the same as names known to exist for botanical or microbiological genera. In the case of a new family-group name the citation of the type genus is mandatory [Art. 16.2], and the author and date of the type genus should be given.
6. The scientific names of genus- or species-group taxa should be printed in a type-face (font) different from that used in the text; such names are usually printed in italics, which should not be used for names of higher taxa. Species¬group names always begin with a lower-case letter, and when cited should always be preceded by a generic name (or an abbreviation of one); names of all supraspecific taxa begin with an upper-case (capital) letter.
7. If a new nominal taxon is established in a work written in a language which is not in wide international use for scientific purposes, the work should include an abstract which draws attention to the new name and which is written in a widely understood language.
8. New names should be established in a work which is printed on paper, which is self-evidently published in the meaning of the Code and has a wide circulation, and which zoologists would not regard as unlikely to contain new names in the taxonomic field concerned. Names should not be established in keys, tables, abstracts, footnotes or similar items subsidiary to the main text of the work.
9. Authors and editors should ensure that all new scientific names are brought to the attention of Zoological Record (which is published by BIOSIS, U.K.), and thus of a wide circle of zoologists.
Citation of names
10. An author who mentions the name of a taxon in the species, genus or family group should cite its authorship and date at least once in the work concerned. A name should not be cited in advance of its intended establishment (see also Appendix A, the "Code of Ethics"), and should not be called "new" except on the occasion of its establishment.
11. After its first mention in a particular work (apart from its possible mention in the title), a genus-group name may be cited in an abbreviated form when in a binomen or trinomen. Such abbreviations should be made unambiguous by (1) always being followed by a full stop (period) and (2) not having a form which could be mistaken for an abbreviation of a related genus-group name (e.g., A. could stand for Aedes or Anopheles, and so would be ambiguous in a work on mosquitoes). Subject to the same considerations, the specific name may be abbreviated in a trinomen (e.g. the names of subspecies of Danaus plexippus could be abbreviated as D. p. plexippus and D. p. menippe).
12. The surnames (family names) of authors of scientific names should not be abbreviated. However, when a name was published by more than three authors, the surname of the first author (as given in the original publication) may be cited alone in the text and followed by the term "et al." (meaning "and others"); the names of all the authors should be cited in the bibliography.