In biology, a monotypic taxon is a taxonomic group which contains only one immediately subordinate taxon. Although the phrase appears to indicate that a taxon has a single type specimen (with no syntypes, lectotypes, or other types), this is not the usage.
An example is the family Cephalotaceae, with only one genus, Cephalotus, and only one species: Cephalotus follicularis, the Albany Pitcher Plant.
In the case of monotypic genera, the term unispecific is sometimes preferred.
A monotypic species is one that does not include subspecies (or other infraspecific taxa).
In taxonomy 
One can also say that the contained taxon is monotypic within the larger taxon; a genus monotypic within a family.
- The genus Tarsius is monotypic within the family Tarsiidae, which is itself monotypic in the Tarsiiformes.
- The Hyacinth Macaw (Anodorhynchus hyacinthinus) is a monotypic species; no subspecies have been distinguished within the species.
- The Bearded Reedling (Panurus biarmicus) has a few subspecies across its range, but belongs to the genus Panurus which current knowledge considers monotypic (the only genus) within the family Panuridae.
Conservation biology 
The monotypic habitat occurs in botanical and zoological contexts. In restoration ecology of native plant communities or habitats, some invasive species create monotypic stands that replace and/or prevent other species, especially indigenous ones, from growing there. A dominant colonization can occur from retardant chemicals exuded, nutrient monopolization, or from lack of natural controls such as herbivores or climate, that keep them in balance with their native habitats.
- A botanical example of a monotypic habitat is that of the yellow starthistle, Centaurea solstitialis, which currently dominates over 15,000,000 acres (61,000 km2) in California alone.
- A zoological example of a monotypic habitat is created by the non-native freshwater zebra mussel, Dreissena polymorpha, which colonizes areas of the Great Lakes and the Mississippi River watershed. A single female can produce upwards of one million eggs per year – without its home-range predator control, it thus chokes out competing flora.
See also 
- Race (classification of human beings) (a more detailed definition of monotypes in the context of humans, Homo sapiens)
- Conservation biology
- Category:Monotypic genera
- Mayr E, Ashlock PD. (1991): Principles of Systematic Zoology (2nd ed.). McGraw-Hill. ISBN 0-07-041144-1
- McNeill, J.; Barrie, F.R.; Buck, W.R.; Demoulin, V.; Greuter, W.; Hawksworth, D.L.; Herendeen, P.S.; Knapp, S.; Marhold, K.; Prado, J.; Reine, W.F.P.h.V.; Smith, G.F.; Wiersema, J.H.; Turland, N.J. (2012). International Code of Nomenclature for algae, fungi, and plants (Melbourne Code) adopted by the Eighteenth International Botanical Congress Melbourne, Australia, July 2011. Regnum Vegetabile 154. A.R.G. Gantner Verlag KG. ISBN 978-3-87429-425-6. article 38.6
- Theel Heather J., Dibble Eric D., Madsen John D. (1948). "Differential influence of a monotypic and diverse native aquatic plant bed on a macroinvertebrate assemblage; an experimental implication of exotic plant induced habitat". Cat.Inist and Springer, Dordrecht, PAYS-BAS. Retrieved 2011-04-17.
- PDF (286 KiB), Mount Diablo Interpretive Association. Retrieved on 2008-10-15.
- 1970 distribution of yellow starthistle in the U.S., a map from UCD's Yellow Starthistle Information website