holotypy

Holotypy is the practice of designating a holotype, a single specimen that serves as the primary reference for the description and name of a newly described taxon. The holotype anchors the species identity and provides a concrete standard against which other specimens are compared.

In most zoological and botanical codes, a holotype must be a single specimen. If multiple specimens were used in the description, they are called paratypes. If no holotype was designated, the name may be linked to syntypes, and a lectotype can later be selected from the original material to serve as the name-bearing type; if the original material is lost or destroyed, a neotype may be designated. The holotype is usually deposited in a recognized public institution, such as a museum or herbarium, and is accompanied by data on collection locality, date, collector, and other relevant information to enable future examination.

Designation of a holotype can occur in the original publication describing the taxon or in a subsequent act that fixes the holotype. The holotype remains the reference point for identifying the taxon, and modern research may utilize data from the holotype, including modern imaging or, in some cases, genetic information, within the constraints of code provisions.

Holotypy contributes to nomenclatural stability by providing a concrete, verifiable reference for the taxon. It applies to living and fossil taxa and to infraspecific ranks, and is a foundational concept in taxonomy and systematic biology.