Catalogue of Type Specimens in the Agriculture and Agri-Food Canada National Collection of Vascular Plants (DAO)

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Catalogue

(Date Modified March-22-2004)



What is a type specimen?

It is the specimen selected by a botanist as an example of a particular species (and/or category of plants). Current international rules of naming plants require that a new name of a newly discovered species is supported by a type specimen in a recognized collection. The type is frequently the most clear indication of what a plant name represents and types are often examined so that plant names can be properly applied.

Several kinds of types are officially recognized in the International Code of Botanical Nomenclature

  • A holotype of a name of a species or infraspecific taxon is the one specimen or illustration used by the author, or designated by the author as the nomenclatural type. As long as a holotype is extant, it fixes the application of the name concerned.
  • An isotype is any duplicate of the holotype; it is always a specimen.
  • A lectotype is a specimen or illustration designated from the original material as the nomenclatural type, if no holotype was indicated at the time of publication, or if it is missing, or if it is found to belong to more than one taxon.
  • A paratype is a specimen cited in the protologue that is neither the holotype nor an isotype, nor one of the syntypes if two or more specimens were simultaneously designated as types.
  • A syntype is any specimen cited in the protologue when there is no holotype, or any one of two or more specimens simultaneously designated as types.
  • A neotype is a specimen or illustration selected to serve as nomenclatural type if no original material is extant, or as long as it is missing.
  • An epitype is a specimen or illustration selected to serve as an interpretative type when the holotype, lectotype, or previously designated neotype, or all original material associated with a validly published name, is demonstrably ambiguous and cannot be critically identified for purposes of the precise application of the name of a taxon. When an epitype is designated, the holotype, lectotype, or neotype that the epitype supports must be explicitly cited

Reference

McNeill, J., F. R. Barrie, H. M. Burdet, V. Demoulin, D. L. Hawksworth, K. Marhold, D. H. Nicholson, J. Prado, P. C. Silva, J. E. Skog, J. H. Wiersema & N. J. Turland. 2006. International Code of Botanical Nomenclature (Vienna Code). Regnum Vegetabile 146. A.R.G. Gantner Verlag KG. ISBN 0080-0694


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Catalogue of Type Specimens in the Vascular Plant Herbarium (PDF Version, 1187 KB)