International Code of Botanical Nomenclature

(Tokyo Code), Electronic version



Article 8

8.1. The type of a name of a species or infraspecific taxon is a single specimen or illustration except in the following case: for small herbaceous plants and for most non-vascular plants, the type may consist of more than one individual, which ought to be conserved permanently on one herbarium sheet or in one equivalent preparation (e.g., box, packet, jar, microscope slide).

8.2. Type specimens of names of taxa must be preserved permanently and cannot be living plants or cultures.

Ex. 1. The strain CBS 7351, given as the type of the name Candida populi Hagler & al. (in Int. J. Syst. Bacteriol. 39: 98. 1989), is acceptable as a nomenclatural type as it is permanently preserved in a metabolically inactive state by lyophilization (see also Rec. 8B.2).

8.3. If it is impossible to preserve a specimen as the type of a name of a species or infraspecific taxon of non-fossil plants, or if such a name is without a type specimen, the type may be an illustration.

8.4. The type of the name of a taxon of fossil plants of the rank of species or below is the specimen whose figure either accompanies or is cited in the valid publication of the name (see Art. 38). If figures of more than one specimen were given or cited when the name was validly published, one of those speci-mens must be chosen as the type.

8.5. One whole specimen used in establishing a taxon of fossil plants is to be considered the nomenclatural type.

Recommendation 8A

8A.1. When a holotype, a lectotype or a neotype is an illustration (see Art. 8.3), the specimen or specimens upon which that illustration is based should be used to help determine the application of the name.

8A.2. When it is impossible to preserve a type specimen and an illustration is designated as the type of the name of a new taxon (see Art. 8.3), 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 coal-ball plants, etc.), all parts originally used in establishing the diagnosis ought to be clearly marked.

Recommendation 8B

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. 8.2.)

8B.2. In cases where the nomenclatural type is a culture permanently preserved in a metabolically inactive state (see Art. 8 Ex. 1), 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.

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