The rulebook that governs how fungi are named is about to undergo its next scheduled revision, and the mycological community has a defined window in which to shape it. Chapter F of the International Code of Nomenclature for algae, fungi, and plants, the section of the Code containing provisions that apply solely to fungi, may be altered only by decision of a plenary session of an International Mycological Congress acting on a resolution moved by that Congress’s Fungal Nomenclature Session. With the XIII International Mycological Congress scheduled for Incheon, Korea in August 2027, the procedures and timetable for submitting proposals to amend Chapter F have now been set out, establishing a submission deadline of 31 December 2026 and a pathway that runs through publication, a synopsis, a guiding vote and a formal session before a revised edition appears in early 2028.
The current Chapter F was incorporated directly into the Madrid Code, the present edition of the Code, which was published on 25 July 2025 in print, eBook and PDF editions and on 4 September 2025 in an open-access interactive online edition. It includes modifications to the preceding version, known as the San Juan Chapter F, and those amendments were adopted on 15 August 2024 at IMC12 in Maastricht, the Netherlands. The Madrid Code thus represents the baseline text against which any proposal for Incheon must be drafted. Governance of the amendment process rests with several interlocking bodies. The International Mycological Congress, organised by the International Mycological Association, provides the ultimate decision-making forum, while the Fungal Nomenclature Bureau organises and runs the Fungal Nomenclature Session and the pre-Congress guiding vote. The Nomenclature Committee for Fungi, elected at the Session, advises on proposals but does not decide on them, and the Editorial Committee for Fungi, also elected at the Session, makes the necessary changes to Chapter F based on formal proposals accepted there.
The Bureau’s leadership for the Incheon Congress is already in place. Tom W. May was re-elected Secretary of the Fungal Nomenclature Bureau for IMC13 at IMC12 in Maastricht, and in a ballot of the Nomenclature Committee for Fungi in March 2025, Konstanze Bensch was confirmed as Deputy Secretary on the suggestion of the Secretary and after consultation with the General Committee. The Deputy Secretary fulfils a role equivalent to the Vice-rapporteur in the Bureau of Nomenclature of an International Botanical Congress, and the procedures of the Fungal Nomenclature Session closely mirror those of the Nomenclature Section of such a Congress, with one notable exception: no institutional votes are utilised at the fungal session. Instead, decisions rest with the individuals present on the day, whose formal votes on each proposal are then ratified by the plenary session of the Congress.
The amendment procedure itself follows a sequence designed to give the community time to scrutinise every change. After each new version of Chapter F appears, proposals for amendment are published in IMA Fungus, either singly or bundled together. Such proposals may suggest revised wording for existing Articles or Recommendations of Chapter F or introduce new material dealing solely with names of organisms treated as fungi, including fossil fungi. Prior to the next Congress, a Synopsis of proposals assembles all published proposals, arranged by Article and Recommendation, and re-publishes them in IMA Fungus. The synopsis omits the justification that accompanied the original publication but instead offers a commentary from the Secretary and Deputy Secretary of the Bureau from a technical perspective, with particular attention to the clarity of wording, implications for other articles and any unintended consequences. It also includes the opinions of relevant bodies such as the Nomenclature Committee for Fungi.
A pre-Congress guiding vote is then held online, commencing shortly after the synopsis is published. The guiding vote is a non-binding indication of the views of those entitled to participate, principally members of the International Mycological Association, authors of proposals and members of the Nomenclature Committee for Fungi. Eligible voters will be contacted either directly by the Secretary of the Bureau or through the Association or relevant societies, and the outcomes are made available on the IMA website in advance of the Session. At the Fungal Nomenclature Session itself, convening during the Congress, the published proposals are considered, including any amendments to them, and for each proposal a formal vote amongst those individuals present on the day is taken. Decisions of the Session are ratified by vote of the plenary session of the Congress, at which point the amended provisions take effect. The new version of Chapter F, incorporating the changes accepted at the Congress, is prepared by the Editorial Committee for Fungi in consultation with the Editorial Committee for the Code as a whole, and the online version of the Code is amended with a note pointing to the new edition.
The timetable for the Incheon cycle is compact. Proposals must be submitted by 31 December 2026, with the Synopsis of proposals published in March 2027, the guiding vote held in May 2027, its results released in June 2027, and the Fungal Nomenclature Session taking place at IMC13 in August 2027. Publication of the revised Incheon Chapter F is expected in early 2028. Submission is now open, and proposals are to be sent by e-mail to the Secretaries of the Bureau. Late submissions received by 31 January 2027 may be accepted if they require neither review nor substantial editing, but proposals that fail to follow the published instructions may be rejected for that reason. After editing, proposals will be made available on the IMA website and published in IMA Fungus under the Nomenclature category, with each proposal assigned a sequential number. There is no article-processing charge for items accepted for publication in that category, and depending on the number, length and timing of submissions, individual proposals and their accompanying justifications may be published separately or grouped together, as was the case prior to the preceding Congress.
The drafting rules are precise, and they exist to ensure that every proposal can be evaluated and implemented without ambiguity. Proposals must be based on the text of Chapter F of the Madrid Code. Each proposal should include an initial summarising paragraph, an assessment of the impact of the proposal on the stability of nomenclature, and some general explanation of the rationale. Proposals must be presented concisely and may be condensed by the Secretaries or journal editors. Each proposal must state explicitly what amendment is proposed, for example inserting a new Article after Art. F.6, deleting Art. F.10, or amending Rec. F.5A.1 with new text shown in bold and deleted text in strikethrough. Proposals must not consist simply of new text or explanation but should indicate precisely what text is to be inserted, deleted or changed, which can be achieved by copying and pasting the relevant passage from the online edition of the Madrid Code and then marking new text in bold. Titles should state the aim of the proposal rather than merely referring to the numbering of the Code, so a title such as Proposals to permit naming of organisms known only from DNA sequences is preferred over one that simply cites Article numbers.
Several further provisions shape how proposals travel through the system. If a proposal results from a more general context, authors must make that context the subject of a separate paper submitted to IMA Fungus or another journal, reviewed in the normal way, with the associated proposal submitted separately by e-mail and cross-referencing the paper. In the case of a Special-purpose Committee, a report summarising the Committee’s work should be submitted to IMA Fungus in the Nomenclature category, providing context and justification for any associated proposals. One such committee has been established to report to the Incheon Congress: the Special-purpose Committee on Genomes as Types for Fungi, with Marco Thines as Convenor and Nathan Schoutteten as Secretary. The Editorial Committee for Fungi can insert, delete or change Examples and Glossary entries without a formal proposal, so proposals concerning Examples or Glossary entries need not be published in IMA Fungus unless they are essential for understanding a proposal to amend an Article, Note or Recommendation; instead they may be submitted at any time directly to the Committee, which prior to the Congress is represented by the Secretaries of the Bureau.
The guidance on what is likely to succeed reflects a long-standing preference for stability and simplicity. Proposals that contribute to nomenclatural stability are more likely to be successful, as are proposals that reduce the complexity of the Code without negatively affecting stability. Proposals addressing nomenclatural situations that occur only rarely are unlikely to succeed, particularly if they add to the complexity of Chapter F; such situations may be better addressed through the conservation or rejection of a particular name, suppression of a particular work, a request for a binding decision on a particular matter, or a new Example in Chapter F. Authors are encouraged to provide a list of all the provisions of Chapter F believed to be affected by a given proposal, helping the Editorial Committee ensure that any amendments adopted are fully integrated with the existing text. If Examples are included, they must follow the format used in Chapter F of the Madrid Code, with places of publication cited in full and links provided to online versions of those publications and the protologues of any basionyms, replaced synonyms or names causing illegitimacy, drawing on resources such as the Biodiversity Heritage Library, Gallica, Google Books and HathiTrust. For publications not yet available online, a scanned copy of the relevant pages, including title pages, is requested.
One final rule addresses proposals whose reach extends beyond fungi. Some proposals concerning fungi may be equally applicable to all organisms covered by the Code or to taxonomic groups broader than fungi alone, and if such proposals are submitted for consideration by the Incheon Session they should be formulated so as to be restricted to fungi. Proposals to amend the Code that are not specific to fungi should instead be submitted to the journal Taxon by 31 March 2028, for consideration by the Nomenclature Section of the XXI International Botanical Congress in 2029. The separation keeps the two amendment streams aligned with their respective Congresses while allowing ideas that originated in mycology to enter the broader nomenclatural conversation through the appropriate channel. For mycologists, the message is clear: the window for shaping the next Chapter F is open now, and the text that emerges from Incheon will be built from proposals that{
Subject of Research: Procedures and timetable for proposals to amend the fungal nomenclature rules of the International Code of Nomenclature for algae, fungi, and plants
Article Title: Procedures and timetable for proposals to amend Chapter F of the International Code of Nomenclature for algae, fungi, and plants
Article References: May, T. W., & Bensch, K. (2026). Procedures and timetable for proposals to amend Chapter F of the International Code of Nomenclature for algae, fungi, and plants. IMA Fungus, 17, Article e195573. https://doi.org/10.3897/imafungus.17.195573
Image Credits: AI Generated
DOI: 10.3897/imafungus.17.195573
Keywords: fungal nomenclature, Chapter F, International Code of Nomenclature, International Mycological Congress, IMC13, Incheon, Fungal Nomenclature Session, Fungal Nomenclature Bureau, guiding vote, IMA Fungus, Madrid Code, taxonomy
News Source: Roger Howard. (October 18, 2026). Fungal naming rules face their next rewrite as mycologists open proposals for 2027 Congress. Scienmag.
