Article 35. The family group
The family group encompasses all nominal taxa at the ranks of superfamily, family, subfamily, tribe, subtribe, and any other rank below superfamily and above genus that may be desired (see also Article 10.3 for collective groups and ichnotaxa).
Family-group nominal taxa and their names are subject to the same provisions whatever their rank, except in respect of their suffixes [Art. 29.2] (for the application of the Principle of Coordination to family-group names, see Article 36).
35.4.1. A family-group name based upon an unjustified emendation (but see Article 35.4.2) or an incorrect spelling of the name of the type genus must be corrected, unless it is preserved under Article 29.5 or unless the spelling of the genus-group name used to form the family-group name is preserved under Articles 18.104.22.168 or 33.3.1.
Example. Goldfuss (1820) published the family-group name Phascolomyda, based on the incorrect spelling Phascolomys (introduced by Duméril, 1806) of Phascolomis Geoffroy, 1803 (Mammalia). The corrected name is PHASCOLOMIDAE Goldfuss, 1820.
35.4.2. If an unjustified emendation of the name of the type genus becomes its substitute name, the family-group name is then to be based on it by correcting the name to the spelling formed from the stem of the substitute name, or the whole substitute name [Art. 29.1]; the author and date of the family-group name remain unchanged.
If after 1999 a name in use for a family-group taxon (e.g. for a subfamily) is found to be older than a name in prevailing usage for a taxon at higher rank in the same family-group taxon (e.g. for the family within which the older name is the name of a subfamily) the older name is not to displace the younger name.
Example. The subfamily ROPHITINAE Schenck, 1866 (Hymenoptera) is universally included in the family HALICTIDAE Thomson, 1869, even though on priority alone the name of the family would be ROPHITIDAE. The precedence of HALICTIDAE over ROPHITIDAE is to be maintained as long as they are treated as subjective synonyms (at family rank), and HALICTINAE and ROPHITINAE are used for different subfamilies within the HALICTIDAE.