Legion (taxonomy)

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The hierarchy of biological classification's eight major taxonomic ranks. Intermediate minor rankings are not shown. Biological classification L Pengo vflip.svg DomainKingdomClassOrderFamily
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

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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Linnaean taxonomy Rank based classification system for organisms

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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.


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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