What is a Type Specimen?

A type specimen is a preserved specimen selected to serve as a permanent reference point for a scientific plant name. Type specimens are vitally important to botanists in determining the correct application of botanical names. There are a number of different categories of types recognised under the International Code of Botanical Nomenclature (the ICBN):

Holotype: The single specimen designated as the type of a species by the original author at the time the species name and description was published.

Isotype: A duplicate specimen of the holotype.

Syntype: Any of two or more specimens listed in the original description of a taxon when a holotype was not designated. Isosyntypes are duplicates of a syntype.

Lectotype: A specimen chosen by a later researcher to serve as the primary type. It is chosen from among the specimens available to the original author of a name when the holotype was either lost or destroyed, or when no holotype was designated. Isolectotypes are duplicates of a lectotype.

Neotype: A specimen chosen by a later researcher to serve in place of a holotype when all specimens available to the original author of a name have been lost or destroyed. Isoneotypes are duplicates of a lectotype.

You may also see references to the following categories that have no standing under the ICBN:

Paratype: A specimen not formally designated as a type but cited along with the type collection in the original description of a taxon.

Topotype: A specimen of a plant collected from the same locality as the holotype, not necessarily at the same time.

Cotype: An old term used by some authors for additional (different) specimens that supported their taxonomic concept.

Lectoparatype: A name sometimes used for the unselected remainder when a lectotype is selected from a number of syntypes.