Paratype

In zoology and botany, a paratype is a specimen of an organism that helps define what the scientific name of a species and other taxon actually represents, but it is not the holotype (and in botany is also neither an isotype nor a syntype). Often there is more than one paratype. Paratypes are usually held in museum research collections.

The exact meaning of the term paratype when it is used in zoology is not the same as the meaning when it is used in botany. In both cases however, this term is used in conjunction with holotype.

In zoological nomenclature, a paratype is officially defined as "Each specimen of a type series other than the holotype."

In turn, this definition relies on the definition of a "type series." A type series is the material (specimens of organisms) that was cited in the original publication of the new species or subspecies, and was not excluded from being type material by the author (this exclusion can be implicit, e.g., if an author mentions "paratypes" and then subsequently mentions "other material examined," the latter are not included in the type series), nor referred to as a variant, or only dubiously included in the taxon (e.g., a statement such as "I have before me a specimen which agrees in most respects with the remainder of the type series, though it may yet prove to be distinct" would exclude this specimen from the type series).

Thus, in a type series of five specimens, if one is the holotype, the other four will be paratypes.

A paratype may originate from a different locality than the holotype. A paratype cannot become a lectotype, though it is eligible (and often desirable) for designation as a neotype.

The International Code of Zoological Nomenclature (ICZN) has not always required a type specimen, but any species or subspecies newly described after the end of 1999 must have a designated holotype or syntypes.

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