In 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...

, a trinomen (plural: trinomina), or trinominal name, refers to the name of a subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...


A trinomen is a name consisting of three names: generic name, specific name and subspecific name
Subspecific name
In zoological nomenclature, a subspecific name is the third part of a trinomen. In zoology there is only one rank below that of species, namely "subspecies"....

. The first two parts alone form the binomen
In zoological nomenclature, a binomen , is the two-part name of a species. The term was introduced in 1953, abolishing the previously used "binomial name" . A binomen consists of a generic name and a specific epithet...

 or 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...

 name. All three names are typeset in italics, and only the generic name is capitalised. No indicator of rank is included: in 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...

, subspecies is the only rank below that of species.
Buteo jamaicensis borealis is one of the subspecies of the red-tailed hawk
Red-tailed Hawk
The Red-tailed Hawk is a bird of prey, one of three species colloquially known in the United States as the "chickenhawk," though it rarely preys on standard sized chickens. It breeds throughout most of North America, from western Alaska and northern Canada to as far south as Panama and the West...

. (Buteo jamaicensis).

If the generic and specific name have already been mentioned in the same paragraph, they are often abbreviated to initial letters: for example one might write, "The Great Cormorant
Great Cormorant
The Great Cormorant , known as the Great Black Cormorant across the Northern Hemisphere, the Black Cormorant in Australia and the Black Shag further south in New Zealand, is a widespread member of the cormorant family of seabirds...

 Phalacrocorax carbo has a distinct subspecies in Australasia
Australasia is a region of Oceania comprising Australia, New Zealand, the island of New Guinea, and neighbouring islands in the Pacific Ocean. The term was coined by Charles de Brosses in Histoire des navigations aux terres australes...

, the Black Shag P. c. novaehollandiae".

In a taxonomic
Alpha taxonomy
Alpha taxonomy is the discipline concerned with finding, describing and naming species of living or fossil organisms. This field is supported by institutions holding collections of these organisms, with relevant data, carefully curated: such institutes include natural history museums, herbaria and...

 publication, a name is incomplete without an author citation and publication details. This indicates who published the name; in what publication; with the date of the publication.
Phalacrocorax carbo novaehollandiae Stephens, 1826

While binomial nomenclature came into being and immediately gained widespread acceptance in the mid-18th century, it was not until the early 20th century that the current unified standard of trinominal nomenclature was agreed upon, mainly due to its tireless promotion by Elliott Coues
Elliott Coues
Elliott Coues was an American army surgeon, historian, ornithologist and author.Coues was born in Portsmouth, New Hampshire. He graduated at Columbian University, Washington, D.C., in 1861, and at the Medical school of that institution in 1863...

 – even though trinomina in the modern usage were pioneered in 1828 by Carl Friedrich Bruch
Carl Friedrich Bruch
Carl Friedrich Bruch was a German ornithologist.In 1828, he proposed a system of trinomial nomenclature for species, in contrast to the binomial system of Carolus Linnaeus....

 and around 1850 widely used especially by Hermann Schlegel
Hermann Schlegel
Hermann Schlegel was a German ornithologist and herpetologist.-Early life and education:Schlegel was born at Altenburg, the son of a brassfounder. His father collected butterflies, which stimulated Schlegel's interest in natural history...

 and John Cassin
John Cassin
John Cassin was an American ornithologist.He is considered to be one of the giants of American ornithology, and was America's first taxonomist, describing 198 birds not previously mentioned by Alexander Wilson and John James Audubon...

. As late as the 1930s, the use of trinomina was not fully established in all fields of zoology. Thus, when referring especially European works of the preceding era, the nomenclature used is usually not in accord with contemporary standards.

See also

  • Trinomial nomenclature
    Trinomial nomenclature
    In biology, trinomial nomenclature refers to names for taxa below the rank of species. This is different for animals and plants:* for animals see trinomen. There is only one rank allowed below the rank of species: subspecies....

  • Binomial nomenclature
    Binomial nomenclature
    Binomial 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...

  • Infraspecific name (botany)
    Infraspecific name (botany)
    In botany, an infraspecific name is the name for any taxon below the rank of species, i.e. an infraspecific taxon. The scientific names of plants are regulated by the International Code of Botanical Nomenclature...

  • Forms in zoological literature
    Forms in zoological literature
    In zoology the term forma is an informal term; under the International Code of Zoological Nomenclature it has no standing ....

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.