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Holotype with red type label affixed AgriasPhlacidonBertradiF2.JPG
Holotype with red type label affixed
Holotype of Marocaster coronatus, MHNT Marocaster coronatus MHNT.PAL.2010.2.2 (Close up).jpg
Holotype of Marocaster coronatus , MHNT

A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several examples, but explicitly designated as the holotype. Under the International Code of Zoological Nomenclature (ICZN), a holotype is one of several kinds of name-bearing types. In the International Code of Nomenclature for algae, fungi, and plants (ICN) and ICZN, the definitions of types are similar in intent but not identical in terminology or underlying concept.


For example, the holotype for the butterfly Plebejus idas longinus is a preserved specimen of that subspecies, held by the Museum of Comparative Zoology at Harvard University. In botany, an isotype is a duplicate of the holotype, where holotype and isotypes are often pieces from the same individual plant or samples from the same gathering.

A holotype is not necessarily "typical" of that taxon, although ideally it is. Sometimes just a fragment of an organism is the holotype, particularly in the case of a fossil. For example, the holotype of Pelorosaurus humerocristatus (Duriatitan), a large herbivorous dinosaur from the early Jurassic period, is a fossil leg bone stored at the Natural History Museum in London. Even if a better specimen is subsequently found, the holotype is not superseded.

Replacements for holotypes

Modern holotype label for Encarsia accenta Encarsia accenta holotype slide.jpg
Modern holotype label for Encarsia accenta

Under the ICN, an additional and clarifying type could be designated an epitype under article 9.8, where the original material is demonstrably ambiguous or insufficient.

A conserved type (ICN article 14.3) is sometimes used to correct a problem with a name which has been misapplied; this specimen replaces the original holotype.

In the absence of a holotype, another type may be selected, out of a range of different kinds of type, depending on the case, a lectotype or a neotype.

For example, in both the ICN and the ICZN a neotype is a type that was later appointed in the absence of the original holotype. Additionally, under the ICZN the commission is empowered to replace a holotype with a neotype, when the holotype turns out to lack important diagnostic features needed to distinguish the species from its close relatives. For example, the crocodile-like archosaurian reptile Parasuchus hislopi Lydekker, 1885 was described based on a premaxillary rostrum (part of the snout), but this is no longer sufficient to distinguish Parasuchus from its close relatives. This made the name Parasuchus hislopi a nomen dubium . Indian-American paleontologist Sankar Chatterjee proposed that a new type specimen, a complete skeleton, be designated. [1] The International Commission on Zoological Nomenclature considered the case and agreed to replace the original type specimen with the proposed neotype. [2]

The procedures for the designation of a new type specimen when the original is lost come into play for some recent, high-profile species descriptions in which the specimen designated as the holotype was a living individual that was allowed to remain in the wild (e.g. a new species of capuchin monkey, genus Cebus, [3] Marleyimyia xylocopae , or the Arunachal macaque Macaca munzala [4] ). In such a case, there is no actual type specimen available for study, and the possibility exists that—should there be any perceived ambiguity in the identity of the species—subsequent authors can invoke various clauses in the ICZN Code that allow for the designation of a neotype. Article 75.3.7 of the ICZN [5] requires that the designation of a neotype must be accompanied by "a statement that the neotype is, or immediately upon publication has become, the property of a recognized scientific or educational institution, cited by name, that maintains a research collection, with proper facilities for preserving name-bearing types, and that makes them accessible for study", but there is no such requirement for a holotype.

See also

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<span class="mw-page-title-main">International Code of Zoological Nomenclature</span> Code of scientific nomenclature for animals

The International Code of Zoological Nomenclature (ICZN) is a widely accepted convention in zoology that rules the formal scientific naming of organisms treated as animals. It is also informally known as the ICZN Code, for its publisher, the International Commission on Zoological Nomenclature. The rules principally regulate:

Type species Term used in biological nomenclature

In zoological nomenclature, a type species is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen(s). A similar concept is used for suprageneric groups and called a type genus.

Type (biology) Specimen(s) to which a scientific name is formally attached

In biology, a type is a particular specimen of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to anchor or centralize the defining features of that particular taxon. In older usage, a type was a taxon rather than a specimen.

<span class="mw-page-title-main">Type genus</span> Term in biological taxonomy

In biological taxonomy, the type genus is the genus which defines a biological family and the root of the family name.

Arunachal macaque Species of Old World monkey

The Arunachal macaque is a macaque native to Arunachal Pradesh in North-east India. It is listed as Endangered on the IUCN Red List. It was scientifically described in 2005.

In binomial nomenclature, a nomen dubium is a scientific name that is of unknown or doubtful application.

In biological nomenclature, a syntype is any one of two or more biological types that is listed in a description of a taxon where no holotype was designated. Precise definitions of this and related terms for types have been established as part of the International Code of Zoological Nomenclature and the International Code of Nomenclature for algae, fungi, and plants.

Nomenclature codes or codes of nomenclature are the various rulebooks that govern biological taxonomic nomenclature, each in their own broad field of organisms. To an end-user who only deals with names of species, with some awareness that species are assignable to families, it may not be noticeable that there is more than one code, but beyond this basic level these are rather different in the way they work.

In botany, an infraspecific name is the scientific name for any taxon below the rank of species, i.e. an infraspecific taxon or infraspecies. The scientific names of botanical taxa are regulated by the International Code of Nomenclature for algae, fungi, and plants (ICN). This specifies a 'three part name' for infraspecific taxa, plus a 'connecting term' to indicate the rank of the name. An example of such a name is Astrophytum myriostigma subvar. glabrum, the name of a subvariety of the species Astrophytum myriostigma.

In biology, a homonym is a name for a taxon that is identical in spelling to another such name, that belongs to a different taxon.

A conserved name or nomen conservandum is a scientific name that has specific nomenclatural protection. That is, the name is retained, even though it violates one or more rules which would otherwise prevent it from being legitimate. Nomen conservandum is a Latin term, meaning "a name to be conserved". The terms are often used interchangeably, such as by the International Code of Nomenclature for Algae, Fungi, and Plants (ICN), while the International Code of Zoological Nomenclature favours the term "conserved name".

<i>Paleorhinus</i> Extinct genus of reptiles

Paleorhinus is an extinct genus of basal phytosaur known from the Late Triassic of Texas and Wyoming, United States, Bavaria, Germany and possibly Poland. It contains two valid species, the type species: Paleorhinus bransoni and Paleorhinus angustifrons. Paleorhinus had a length of about 2.5 meters.

<i>Parasuchus</i> Extinct genus of reptiles

Parasuchus is an extinct genus of phytosaur known from the Late Triassic of Andhra Pradesh and Madhya Pradesh, India. It contains a single species, Parasuchus hislopi.

Paratype Taxonomic term

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. Often there is more than one paratype. Paratypes are usually held in museum research collections.

The Botanical and Zoological Codes of nomenclature treat the concept of synonymy differently.

Macropterygius is a genus of ichthyosaurs known from the Late Jurassic of England. Though many specimens have been referred to this genus from all over Europe, the type specimen of the only recognized species, M. trigonus, consists of just a single vertebra. Because this cannot be used to distinguish ichthyosaurs from one another, the genus and species are currently considered nomena dubia.

<span class="mw-page-title-main">Taxonomic rank</span> Level in a taxonomic hierarchy

In biological classification, taxonomic rank is the relative level of a group of organisms in an ancestral or hereditary hierarchy. A common system consists of species, genus, family, order, class (clade), phylum, kingdom, domain. The study of taxonomy is also called cladistics.

Under the International Code of Zoological Nomenclature (Code), the name-bearing type is the biological type that determines the application of a name. Each animal 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 one or more type specimens. For example, the name Mabuya maculata has often been used for the Noronha skink, but because the name-bearing type of the former, a lizard preserved in the Muséum national d'histoire naturelle in Paris, does not represent the same species as the Noronha skink, the name maculata cannot be used for the latter.

Urrao antpitta Species of bird

The Urrao antpitta, also known as Fenwick's antpitta, is a highly threatened species of bird found in the understory of cloud forest in the Andean highlands of Colombia. The first published description used the scientific name Grallaria fenwickorum ; shortly afterward, a second description using the name Grallaria urraoensis was published. The editors of the latter recognized that the name likely was a junior synonym, but others have questioned the validity of the first description, and various authorities, including the International Ornithological Congress, have adopted G. urraoensis. Antioquia antpitta has been suggested as an English-language name compromise.

This is a list of terms and symbols used in scientific names for organisms, and in describing the names. For proper parts of the names themselves, see List of Latin and Greek words commonly used in systematic names. Note that many of the abbreviations are used with or without a stop.


  1. Case 3165, Bulletin of Zoological Nomenclature 58:1 Archived 2007-09-28 at the Wayback Machine , 30 March 2001.
  2. Opinion 2045, Bulletin of Zoological Nomenclature 60:2 Archived 2007-09-28 at the Wayback Machine , 30 June 2003.
  3. Mendes Pontes, A.R., Malta A. and Asfora, P.H. 2006. A new species of capuchin monkey, genus Cebus Erxleben (Cebidae, Primates): found at the very brink of extinction in the Pernambuco Endemism Centre. Zootaxa 1200: 1-12.
  4. Sinha, A.,Datta, A., Madhusudan, M. D. and Mishra, C. (2004). "The Arunachal macaque Macaca munzala: a new species from western Arunachal Pradesh, northeastern India". International Journal of Primatology volume: 26 issue: 977 pages: 989.
  5. International Code of Zoological Nomenclature, Art. 75.3.7