Paratype
Encyclopedia
Paratype is a technical term used in the scientific naming of species
and other taxa of organisms. 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 another term, holotype
.
The term refers to type material, an actual specimen or specimens of the organism in question on deposit, usually in a museum research collection, in order to help define what the taxon actually represents. Often there is more than one paratype, although there can be only one 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 syntype
s.
A related term is allotype
, a term that indicates a specimen that exemplifies the opposite sex of the holotype, and is almost without exception designated in the original description, and, accordingly, part of the type series, and thus a paratype; in such cases, it is functionally no different from any other paratype. It has no nomenclatural standing whatsoever, and although the practice of designating an allotype is recognized by the Code, it is not a "name-bearing type
" and there are no formal rules controlling how one is designated. Apart from species exhibiting strong sexual dimorphism
, relatively few authors take the trouble to designate such a specimen. It is not uncommon for an allotype to be a member of an entirely different species from the holotype, because of an incorrect association by the original author.
, nor one of the syntypes if two or more specimens were simultaneously designated as types" (Art. 9.5).
Under this definition, paratypes are not necessarily explicitly identified as such in the original description.
Paratypes are useful in that they allow subsequent botanists to know what collections were examined by the original author and considered part of the same taxon
in preparing the description of a new taxon, particularly when the holotype and isotypes may be unavailable, of poor quality, or lacking in certain details.
Paratypes are also useful in providing one or more collections from which a lectotype may be designated if no holotype, isotype, syntype, or isosyntype is extant (Art. 9.10).
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
and other taxa of organisms. The exact meaning of the term paratype when it is used in zoology
Zoology
Zoology |zoölogy]]), is the branch of biology that relates to the animal kingdom, including the structure, embryology, evolution, classification, habits, and distribution of all animals, both living and extinct...
is not the same as the meaning when it is used in botany
Botany
Botany, plant science, or plant biology is a branch of biology that involves the scientific study of plant life. Traditionally, botany also included the study of fungi, algae and viruses...
. In both cases however, this term is used in conjunction with another term, holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
.
The term refers to type material, an actual specimen or specimens of the organism in question on deposit, usually in a museum research collection, in order to help define what the taxon actually represents. Often there is more than one paratype, although there can be only one holotype.
Zoology
In zoological nomenclature, a paratype is officially defined as "Each specimen of a type series other than the holotypeHolotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as 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
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as 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
Lectotype
In botanical nomenclature and zoological nomenclature, a lectotype is a kind of name-bearing type. When a species was originally described on the basis of a name-bearing type consisting of multiple specimens, one of those may be designated as the lectotype...
, though it is eligible (and often desirable) for designation as a neotype.
The International Code of Zoological Nomenclature
International Code of Zoological Nomenclature
The International Code of Zoological Nomenclature is a widely accepted convention in zoology that rules the formal scientific naming of organisms treated as animals...
(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 syntype
Syntype
In biological nomenclature, a syntype is a term used to indicate a specimen with a special status.In zoological nomenclature, a syntype is defined as "Each specimen of a type series from which neither a holotype nor a lectotype has been designated [Arts. 72.1.2, 73.2, 74]. The syntypes...
s.
A related term is allotype
Allotype
Allotype can refer to:* In zoological nomenclature, an allotype is a specimen of the opposite sex to the holotype, designated from among paratypes * In immunology, an immunoglobulin allotype...
, a term that indicates a specimen that exemplifies the opposite sex of the holotype, and is almost without exception designated in the original description, and, accordingly, part of the type series, and thus a paratype; in such cases, it is functionally no different from any other paratype. It has no nomenclatural standing whatsoever, and although the practice of designating an allotype is recognized by the Code, it is not a "name-bearing type
Name-bearing type
Under the International Code of Zoological Nomenclature , the name-bearing type is the biological type that determines the application of a name. Each taxon regulated by the Code at least potentially has a name-bearing type. The name-bearing type can be either a type genus , type species , or type...
" and there are no formal rules controlling how one is designated. Apart from species exhibiting strong sexual dimorphism
Sexual dimorphism
Sexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...
, relatively few authors take the trouble to designate such a specimen. It is not uncommon for an allotype to be a member of an entirely different species from the holotype, because of an incorrect association by the original author.
Botany
In systematic botany, a paratype is defined by the International Code of Botanical Nomenclature (ICBN) as "a specimen cited in the protologue (i.e., the original description) that is neither the holotype nor an isotypeIsotype
Isotype can refer to:* In crystallography, an "isotype" is a synonym for isomorph* In biology, per the International Code of Botanical Nomenclature, the "isotype" is a duplicate of the holotype....
, nor one of the syntypes if two or more specimens were simultaneously designated as types" (Art. 9.5).
Under this definition, paratypes are not necessarily explicitly identified as such in the original description.
Paratypes are useful in that they allow subsequent botanists to know what collections were examined by the original author and considered part of the same taxon
Taxon
|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...
in preparing the description of a new taxon, particularly when the holotype and isotypes may be unavailable, of poor quality, or lacking in certain details.
Paratypes are also useful in providing one or more collections from which a lectotype may be designated if no holotype, isotype, syntype, or isosyntype is extant (Art. 9.10).
See also
- Biological type
- Scientific name
- Binomial nomenclatureBinomial nomenclatureBinomial nomenclature is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin grammatical forms, although they can be based on words from other languages...