Monotypic is an adjective, that refers to a taxonomic group with only one type:

• in botany it means that a taxon has only one species; Ginkgo is a monotypic genus, while Ginkgoaceae is a monotypic family. The phrase is not really accurate, as it assumes that a species includes only a single type. This is not necessarily the case as a species may include several subspecies (or other infraspecific taxa) each of which will have a type. A more accurate term is "unispecific".

An example is the genus Darlingtonia, with only one species: Darlingtonia californica.

• in zoology "monotypic" refers to a taxon that contains only one immediately subordinate taxon.Mayr E, Ashlock PD. 1991. Principles of Systematic Zoology. Second Edition. Published by McGraw-Hill, inc. ISBN 0-07-041144-1. For example, a monotypic genus has only one species. Conversely, one can say that the contained taxon is monotypic within the larger taxon; a genus monotypic within a family.

An example is the genus Tarsius which is monotypic within the Tarsiidae family (which is itself monotypic in Tarsiiformes).

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