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The U. S. National Arboretum Herbarium (NA) is finishing a long term project of reviewing the TYPE status of specimens held in the NA Nomenclatural Type Collection as well as Horticultural Cultivated Standards (formerly referred to as "CLONOTYPE"; see definitions below).

What is a TYPE Specimen and a Cultivated STANDARD?

• A TYPE specimen is the specimen which formed the basis of the original description. When a botanist names a new plant, he/she must designate one herbarium specimen (or illustration) which had been used to create the new name.
• A Cultivated STANDARD is the designated herbarium specimen, or equivalent element, to which a cultivar name is attached, whether it is an accepted epithet or a synonym, which shows or states the character (feature) which the cultivar is based.

Our Virtual Herbarium Project

It is our intention to electronically capture all of the data associated with each of the Type Specimens, Horticultural Cultivated Standards, as well as Specimens of Special Interest, to image these specimens, and to put all this information on the internet. The review process includes comparing label and annotation data on the herbarium sheets with the original publications. Although we have not finished the project we are close and have posted what we have done. You can review the specimens by following the links above or the drop-down menu links found on all of these Virtual US National Herbarium web pages.

Some Definitions

In order to help clarify or rank TYPE specimens according to their value by the author, different levels of TYPE specimens are designated. They are:

• HOLOTYPE: The one specimen or illustration used by the author or designated by the author as the TYPE for the new name.
• ISOTYPE: Any specimen that is a duplicate of the HOLOTYPE
• LECTOTYPE: A specimen or illustration designated from the original material as the 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.
• ISOLECTOTYPE: Any specimen that is a duplicate of a LECTOTYPE
• SYNTYPE: Any specimen cited in the protologue when no holotype was designated, or any one of two or more specimens simultaneously designated as TYPES
• PARATYPE: Any specimen cited in the protologue that is neither the HOLOTYPE or an ISOTYPE, nor one of the SYNTYPES
• NEOTYPE: A specimen or illustration selected to serve as a nomenclatural type as long as all of the material on which the name of the Taxon was based is missing.
• EPITYPE: A specimen or illustration selected to serve as an interpretive 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.