Taxonomy -- March 1998

The Correct Naming of Carnivorous Plants: ICBN, ICNCP, and the Roles of CPN and ICPS

Jan Schlauer, CPN Editor

Keywords: cultivar -- new taxa.


There is no better way for the transmission of information on a particular plant than to use a name for it that can be translated into a widely agreed definition including the plant and all other plants that are similar. There are several sets of rules governing the proper process of establishment or valid publication of plant names. Differences of opinion are an intrinsic part of the evolution of knowledge and thus also an element in the progress of plant classification. There is no fixed rule on how to coin definitions and this text will not deal with these problems but rather with the question of how to name the different plant groups.

What Do I Have?

Before a name can be given to a plant or group of plants, its nature must be determined. There are two different modes to deal with plants: either the plant in question is part of the biotic evolution in nature (i.e. a representative of a population of individuals) or it is a result of the efforts of a breeder, and deserves particular merits because of desired traits. In the first case, we are dealing with a taxon (plural taxa), in the second case with a cultivated plant. Taxa have a phylogenetic meaning (they are supposed to reflect stages in the natural process of the development of species), and they are named scientifically according to the International Code of Botanical Nomenclature (ICBN). Cultivated plants have a meaning for the plant trade, and they are named according to the International Code for the Nomenclature of Cultivated Plants (ICNCP).

Do I Have Something New?

If a taxon was described already (i.e. if the taxon has been given a valid name according to the ICBN) or if an established name is available for a cultivated plant (according to the ICNCP), the plant must be referred to using this name. No other name may be applied. If no valid or established name is available, the plant may be named by any person. It is the responsibility of such an author to make sure that the plant in question does not belong to a taxon and/or is not a cultivated plant that has received a valid or established name previously (a point where we may enter the difficult region of definition and limits).

How Do I Name Something New?

In order to receive valid names, taxa must be described in a protologue (original description) in Latin language and (if the rank of the taxon is species or below) represented by a conserved specimen (dried or in alcohol), the so-called type. The description should highlight all features defining the new taxon (at least the diagnostic ones which distinguish it from other taxa). The name of a taxon must be in Latin, it must not be identical with a name already published before, and it must conform to the intended rank of the taxon (please refer to the ICBN for the definition of ranks). The description must be published effectively (i.e. in a publicly accessible source of information for botanists), and it must include a reference to the type specimen and to the institution at which the type is stored permanently. In special cases several other rules of the ICBN have to be followed, and all taxonomists should know the entire text of the ICBN (1993) before they publish their first new name.

The naming of cultivated plants is different in some respects. In order to name a cultivated plant, it must be described in a modern language highlighting its differences from other plants. A standard has to be chosen for the cultivated plant. This standard should be a high quality colour photograph for cultivars (see below) of carnivorous plants. There are three categories (called "taxa" in the ICNCP; this term is omitted here because of possible confusion with taxa in the sense of the ICBN) of cultivated plants: cultivars (by far the most common category, and the only one used for carnivorous plants so far), graft-chimaeras, and cultivar-groups (assemblages of two or more cultivars belonging to a ICBN-taxon within which the use of a cultivar name may not be duplicated, the so-called denomination class). Cultivars do not have a taxonomic rank of their own but they belong to the taxon from which they were derived (by cultivation). A cultivar name consists of the scientific name of the taxon it belongs to plus an additional name, the so-called cultivar epithet, which is an expression in a modern language. A cultivar epithet must be different from all cultivar epithets previously established within the respective denomination class. In order to distinguish cultivar epithets from scientific names, cultivar epithets must be written with capital initial letters and they must be enclosed in single quotation marks. An established cultivar name is e.g. Nepenthes mirabilis 'Greenhorn'. Several additional rules, as well as a quick-guide are laid down in the ICNCP (1995), and authors who want to establish new cultivar names should consult this text for further information.


The future registration of taxon names with the International Association for Plant Taxonomy has been announced in this issue of Carnivorous Plant Newsletter (see article on page 25). Cultivar names of carnivorous plants are registered by the ICPS, the forthcoming International Registration Authority for carnivorous plant cultivars. All descriptions of cultivar names submitted to Carnivorous Plant Newsletter will be registered automatically, and no action by the authors is necessary. It is therefore required that all such submissions conform with the ICNCP and the criteria for cultivar registration (incl. names and addresses of the originator, nominant, introducer, and registrant, the respective years, the parentage of the cultivar, particulars of associated patents, trade-marks, or plant breeders' rights, awards received with dates and name of the awarding body). Registration of names established in Carnivorous Plant Newsletter is free of charge, as a service to the members of the ICPS.

In order to be established, all cultivar names of carnivorous plants not established in Carnivorous Plant Newsletter must be registered with the ICPS by submission of the data mentioned in the Notes for IRAs of the ICNCP to one of the co-editors of Carnivorous Plant Newsletter. All expenses arising from registration of names not established in Carnivorous Plant Newsletter will be charged to the registrant.


ICBN 1994 International Code of Botanical Nomenclature (Tokyo Code), Greuter, W., Barrie, F. R., Burdet, H. M., Chaloner, W. G., Demoulin, V., Hawksworth, D. L., Jørgensen, P. M., Nicolson, D. H., Silva, P. C., Trehane, P., and McNeill, J. (eds.), Adopted by the Fifteenth International Botanical Congress, Yokohama, August-September 1993, Regnum Vegetabile 131. Koeltz Scientific Books, Königstein, Germany, ISBN 3-87429-367-X or 1-878762-66-4 or 80-901699-1-0

ICNCP 1995 International Code of Nomenclature for Cultivated Plants, Trehane P., Brickell, C. D., Baum, B. R., Hetterscheid, W. L. A., Leslie, A. C., McNeill, J., Spongberg, S. A., and Vrugtman, F. (eds.), Adopted by the International Commission for the Nomenclature of Cultivated Plants, Regnum Vegetabile 133. Quarterjack Publishing, Wimborne, UK, ISBN 0-948117-01-X

©International Carnivorous Plant Society

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