Nomenclatural type specimens are important elements of botanical nomenclature. The name of a taxon is permanently attached to the type, whether as a correct name or as a synonym. These valuable specimens should be given extra care and protection.

The rules and practice of typification have changed over the years. The current rules and recommendations are detailed in the The International Code of Botanical Nomenclature, ICBN, (Division II, Section 2, Typification, Articles 7, 8, 9, 10). Prior to 1 January 1958 the publication of the new name of a taxon of the rank of genus or below did not require the designation of a type in the publication. References to type specimens in early plant systematics literature are absent or vague. Older specimens often lack complete collection data. Getting these types, specimens and nomenclature sorted out often requires the expertise of a specialist in the plant group and pertinent literature. The specialist is the ideal person to address these problems and provide definitive resolution.

Type specimen annotations require more detail than most other annotations. General information on annotating herbarium specimens may be found in: Annotation of Herbarium Specimens: Recommendations. The following guidelines may be helpful.

  1. Each type should be annotated with the following:
    • The kind of type (see list of type definitions below)
    • The basionym (first valid scientific name applied to a taxon, i.e., the name on which combinations, if any, are based)
    • The complete literature citation
    • The determiner and date
    • Optionally, the institution of the determiner, the project name and relevant comments. E.g., “Isotypes at B, FLAS, M and NY.”
  2. If the currently accepted name differs from the basionym, the specimen should also be annotated with the currently accepted name.

Examples:

The basionym and the currently accepted name are the same:

HOLOTYPE of:
Gongora tridentata Whitten
Lindleyana 6(2): 109-112. 1991.
Norris H. Williams, FLAS 26 Feb 1999
A Monograph of Gongora (Orchidaceae)

The basionym and the currently accepted name are different:

Basionym annotation:

ISOTYPE of:
Andropogon macrourus Michaux var. corymbosus Hackel
DC. Monogr. Phanerog. 6: 409. 1889.
Note: Cited in: Campbell. J. Arn. Arb. 64: 238. 1983.
Kent D. Perkins, FLAS 26 Feb. 1999

Currently accepted name annotation:

Grasses of the World
Andropogon glomeratus (Walter) B.S.P. var. glomeratus
Kent D. Perkins, FLAS 26 Feb. 1999

Combined information on one annotation:

Grasses of the World
Andropogon glomeratus (Walter) B.S.P. var. glomeratus
ISOTYPE of:
Andropogon macrourus Michaux var. corymbosus Hackel
DC. Monogr. Phanerog. 6: 409. 1889.
Note: Cited in: Campbell. J. Arn. Arb. 64: 238. 1983.
Kent D. Perkins, FLAS 26 Feb. 1999

Lectotype annotation, taxon currently treated under transferred name:

Studies in the Melanthiaceae
Anticlea sibirica (Perkins) Zomlefer & Judd
Lectotype of:
Zigadenus sibiricus Perkins, Mongr. Phanerog. 6: 409. 1889.Designated by: Zomlefer, Novon 12(2): 238. 2002.

Type Definitions (based on ICBN, Chapter II, Section 2, Article 9)

* The terms specimen and duplicate are given their usual meaning in herbarium curatorial practice. A specimen and its duplicates are part of a single gathering of a single species or infraspecific taxon made by a collector at one time. Although not specifically stated in ICBN, the specimen and its duplicates should all have the same collector number.

Other Type Terms (these terms are commonly used but are not officially designated in the ICBN)