Subspecies (biology)

In biological classification, the term subspecies refers to a unity of populations of a species living in a subdivision of the species’s global range and varies from other populations of the same species by morphological characteristics. A subspecies cannot be recognized independently. A species is either recognized as having no subspecies at all or at least two, including any that are extinct. The term is abbreviated "subsp." or "ssp."; plural: "subspecies".

In zoology, under the International Code of Zoological Nomenclature, the subspecies is the only taxonomic rank below that of species that can receive a name. In botany and mycology, under the International Code of Nomenclature for algae, fungi, and plants, other infraspecific ranks, such as variety, may be named. In bacteriology and virology, under standard bacterial nomenclature and virus nomenclature, there are recommendations but not strict requirements for recognizing other important infraspecific ranks.

A taxonomist decides whether to recognize a subspecies or not. A common criteria for a subspecies is its ability of interbreeding with a different subspecies of the same species and producing fertile offspring. In the wild, subspecies do not interbreed due to their geographic isolation and sexual selection. The differences between subspecies are less distinct than the differences between species.

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