Code

The International Code of Nomenclature for algae, fungi, and plants, known as the "Code", is a set of internationally agreed rules and recommendations for naming these organisms. Scientific nomenclature has deep historical roots. Indeed, the system of naming organisms is one of the first truly global scientific standards. This important reference traces back to Alphonse de Candolle's 1867 work "Lois de la nomenclature botanique" (Laws of Botanical Nomenclature). The current 2025 edition of the Code, the Madrid Code, reflects decisions made at the Twentieth International Botanical Congress, which took place in Madrid, Spain, in July 2024. The Congress discussed 447 proposals for amendments to the Code and adopted important new rules, including a voluntary registration mechanism for plant and algae names, clarifications regarding names of fossil taxa, the possibility to reject a new name if it is derogatory toward any group of people, and replacement of an epithet that was considered particularly offensive (with afra, afrorum, and afrum).