Legion (taxonomy)

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Legion %28taxonomy%29 LifeDomainKingdomPhylumClassOrderFamilyGenusSpecies
The hierarchy of biological classification's eight major taxonomic ranks. Intermediate minor rankings are not shown.

The legion, in biological classification, is a non-obligatory taxonomic rank within the Linnaean hierarchy sometimes used in zoology.

Taxonomic rank Level in a taxonomic hierarchy

In biological classification, taxonomic rank is the relative level of a group of organisms in a taxonomic hierarchy. Examples of taxonomic ranks are species, genus, family, order, class, phylum, kingdom, domain, etc.

Linnaean taxonomy A rank based classification system for organisms

Linnaean taxonomy can mean either of two related concepts:

  1. the particular form of biological classification (taxonomy) set up by Carl Linnaeus, as set forth in his Systema Naturae (1735) and subsequent works. In the taxonomy of Linnaeus there are three kingdoms, divided into classes, and they, in turn, into orders, genera, and species, with an additional rank lower than species.
  2. a term for rank-based classification of organisms, in general. That is, taxonomy in the traditional sense of the word: rank-based scientific classification. This term is especially used as opposed to cladistic systematics, which groups organisms into clades. It is attributed to Linnaeus, although he neither invented the concept of ranked classification nor gave it its present form. In fact, it does not have an exact present form, as "Linnaean taxonomy" as such does not really exist: it is a collective (abstracting) term for what actually are several separate fields, which use similar approaches.

Zoology is the branch of biology that studies the animal kingdom, including the structure, embryology, evolution, classification, habits, and distribution of all animals, both living and extinct, and how they interact with their ecosystems. The term is derived from Ancient Greek ζῷον, zōion, i.e. "animal" and λόγος, logos, i.e. "knowledge, study".


Taxonomic rank

In zoological taxonomy, the legion is:

  1. subordinate to the class
  2. superordinate to the cohort.
  3. consists of a group of related orders

Legions may be grouped into superlegions or subdivided into sublegions, and these again into infralegions.

Use in zoology

Legions and their super/sub/infra groups have been employed in some classifications of birds and mammals. Full use is made of all of these (along with cohorts and supercohorts) in, for example, McKenna and Bell's classification of mammals. [1]

See also

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Taxonomy (biology) The science of identifying, describing, defining and naming groups of biological organisms

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In biological classification, the order is

  1. a taxonomic rank used in the classification of organisms and recognized by the nomenclature codes. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family. An immediately higher rank, superorder, may be added directly above order, while suborder would be a lower rank.
  2. a taxonomic unit, a taxon, in that rank. In that case the plural is orders.
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Prototheria subclass of mammals

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Mammal classification

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Eocardiidae family of mammals

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Cladotheria legion of mammals

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Neogene of the Old World is a database containing information about Eurasian Miocene to Pleistocene land mammal taxa and localities, with emphasis on the European Miocene and Pliocene.

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  1. McKenna, Malcolm C. and Susan K. Bell (editors). 1997. Classification of Mammals Above the Species Level. New York: Columbia University Press. ISBN   0-231-11013-8