|INTERNATIONAL CODE OF BOTANICAL NOMENCLATURE online|
8.1. The type (holotype, lectotype, or neotype) of a name of a species or infraspecific taxon is either a single specimen conserved in one herbarium or other collection or institution, or an illustration (but see also Art. 37.4 and 37.6 for names published on or after 1 January 1958).
8.2. For the purpose of typification a specimen is a gathering, or part of a gathering, of a single species or infraspecific taxon made at one time, disregarding admixtures (see Art. 9.12). It may consist of a single plant, parts of one or several plants, or of multiple small plants. A specimen is usually mounted on a single herbarium sheet or in an equivalent preparation, such as a box, packet, jar or microscope slide.
8.3. A specimen may be mounted as more than one preparation, as long as the parts are clearly labelled as being part of that same specimen. Multiple preparations from a single gathering that are not clearly labelled as being part of a single specimen are duplicates, irrespective of whether the source was one plant or more than one (but see Art. 8.5).
8.4. Type specimens of names of taxa must be preserved permanently and may not be living plants or cultures. However, cultures of fungi and algae, if preserved in a metabolically inactive state (e.g. by lyophilization or deep-freezing), are acceptable as types.
8.5. The type, epitypes (Art. 9.7) excepted, of the name of a taxon of fossil plants of the rank of species or below is always a specimen (see Art. 9.13). One whole specimen is to be considered as the nomenclatural type (see Rec. 8A.3).
8A.1. When a holotype, a lectotype, or a neotype is an illustration, the specimen or specimens upon which that illustration is based should be used to help determine the application of the name (see also Art. 9.13).
8A.2. When an illustration is designated as the type of a name under Art. 37.5, the collection data of the illustrated material should be given (see also Rec. 32D.2).
8A.3. If the type specimen of a name of a fossil plant is cut into pieces (sections of fossil wood, pieces of coalball plants, etc.), all parts originally used in establishing the diagnosis should be clearly marked.
8A.4. When a single specimen designated as type is mounted as multiple preparations, this should be stated in the protologue, and the preparations appropriately labelled.
8B.1. Whenever practicable a living culture should be prepared from the holotype material of the name of a newly described taxon of fungi or algae and deposited in at least two institutional culture or genetic resource collections. (Such action does not obviate the requirement for a holotype specimen under Art. 8.4.)
8B.2. In cases where the type of a name is a culture permanently preserved in a metabolically inactive state (see Art. 8 Ex. 6), any living isolates obtained from that should be referred to as "ex-type" (ex typo), "ex-holotype" (ex holotypo), "ex-isotype" (ex isotypo), etc., in order to make it clear they are derived from the type but are not themselves the nomenclatural type.
(c) 2006, by International Association for Plant Taxonomy. This page last updated 11.03.2007 .