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International Code of Nomenclature for algae, fungi, and plants

The International Code of Nomenclature for algae, fungi, and plants is the set of rules and recommendations that govern the scientific naming of all organisms traditionally treated as algae, fungi, or plants, whether fossil or non-fossil, including blue-green algae (Cyanobacteria), chytrids, oomycetes, slime moulds, and photosynthetic protists with their taxonomically related non-photosynthetic groups (but excluding Microsporidia). Before 2011 it was called the International Code of Botanical Nomenclature (ICBN).

This edition of the Code embodies the decisions of the Nomenclature Section of the XIX International Botanical Congress (IBC), which took place in Shenzhen, China in July 2017. This Shenzhen Code supersedes the Melbourne Code (McNeill & al. in Regnum Veg. 154. 2012), published after the XVIII IBC in Melbourne, Australia in 2011. The rules of the Shenzhen Code became effective immediately upon acceptance of the resolution at the closing plenary session of the XIX IBC on 29 July 2017, that the decisions and appointments of its Nomenclature Section be approved. The Shenzhen Code in its final form was published on 26 June 2018 (printed version). This electronic version was made available on 27 June 2018. A PDF version was made available to members of the International Association for Plant Taxonomy on 27 January 2019.

Several authorized translations of the Shenzhen Code have been made available and can be accessed at https://www.iaptglobal.org/shenzhen-code. Note that in questions about the meaning of provisions in translated editions of this Code, the English edition is definitive. Automatic translations, such as those provided by some web browsers, may be inaccurate and should not be relied upon.


Provisions of the Code relating solely to names of fungi are gathered together in its Chapter F. The content of Chapter F may be modified by action of the Fungal Nomenclature Session of an International Mycological Congress (IMC). Chapter F was revised as a result of decisions approved on 21 July 2018 by the closing plenary session of the 11th IMC, held in San Juan, Puerto Rico. The resulting San Juan Chapter F was published in the journal IMA Fungus on 27 December 2019 as an open-access article. The San Juan Chapter F supersedes Chapter F of the Shenzhen Code.