Callitriche L.

This genus is accepted, and its native range is Cosmopolitan.


Callitrichaceae, Inga Hedberg & Olov Hedberg. Flora of Tropical East Africa. 2003

The leaf shape and arrangement vary considerably with the habitat of the plant Description as for the family All tropical African material was earlier classified as C. stagnalis Scop., but recent taxonomic work has shown that several species can be recognized based on morphological, pollen and chromosomal differences. The four tropical African species fall well within the range of variation Chromosome counts from European material shows the somatic numbers between 6 and 40 The most useful character for identification is that of ripe fruits The adaptation of the genus to aquatic life has resulted in the reduction of several morphological features, so that only a few reliable characters remain which can be used for identification Terrestrial plants tend to have ovate or suborbicular leaves Submerged plants often have lanceolate or linear leaves and long internodes, while in plants where the shoots reach the surface the internodes tend to be shorter and have rosettes of elliptic or spathulate leaves Other taxonomically useful characters, albeit unsuitable for use in species’ keys, are the morphology of pollen and the number of chromosomes This pattern is present in all tropical African species In pollen, the exine surface shows the Croton pattern, which is a reticulate pattern with processes (clavae) at the intersections of the walls (muri) (Erdtman, G., 1952, Pollen morphology and plant taxonomy: Angiosperms, p. 173)

Native to:

Afghanistan, Alabama, Alaska, Albania, Alberta, Aleutian Is., Algeria, Altay, Amsterdam-St.Paul Is, Amur, Antipodean Is., Argentina Northeast, Argentina Northwest, Argentina South, Arizona, Arkansas, Assam, Austria, Azores, Baleares, Baltic States, Bangladesh, Belarus, Belgium, Bolivia, Borneo, Brazil Northeast, Brazil South, Brazil Southeast, British Columbia, Bulgaria, Burundi, Buryatiya, California, Cameroon, Canary Is., Cape Provinces, Central European Rus, Chatham Is., Chile Central, Chile North, Chile South, China North-Central, China South-Central, China Southeast, Chita, Colombia, Colorado, Connecticut, Corse, Costa Rica, Crozet Is., Cuba, Cyprus, Czechoslovakia, Delaware, Denmark, District of Columbia, Dominican Republic, East Aegean Is., East European Russia, East Himalaya, Ecuador, Eritrea, Ethiopia, Falkland Is., Finland, Florida, France, Føroyar, Galápagos, Georgia, Germany, Great Britain, Greece, Greenland, Guatemala, Heard-McDonald Is., Honduras, Hungary, Iceland, Idaho, Illinois, India, Indiana, Inner Mongolia, Iowa, Iran, Ireland, Irkutsk, Italy, Japan, Jawa, Juan Fernández Is., Kamchatka, Kansas, Kazakhstan, Kentucky, Kenya, Kerguelen, Kermadec Is., Khabarovsk, Kirgizstan, Korea, Krasnoyarsk, Kriti, Krym, Kuril Is., KwaZulu-Natal, Labrador, Lebanon-Syria, Libya, Louisiana, Macquarie Is., Madagascar, Madeira, Magadan, Maine, Manchuria, Manitoba, Marion-Prince Edward, Maryland, Massachusetts, Mexico Central, Mexico Gulf, Mexico Northeast, Mexico Northwest, Mexico Southeast, Mexico Southwest, Michigan, Minnesota, Mississippi, Missouri, Mongolia, Montana, Morocco, Nansei-shoto, Nebraska, Nepal, Netherlands, Nevada, New Brunswick, New Guinea, New Hampshire, New Jersey, New Mexico, New South Wales, New York, New Zealand North, New Zealand South, Newfoundland, North Carolina, North Caucasus, North Dakota, North European Russi, Northwest European R, Northwest Territorie, Norway, Nova Scotia, Nunavut, Ohio, Oklahoma, Ontario, Oregon, Pakistan, Palestine, Paraguay, Pennsylvania, Peru, Poland, Portugal, Primorye, Prince Edward I., Qinghai, Queensland, Québec, Rhode I., Romania, Rwanda, Sakhalin, Sardegna, Saskatchewan, Sicilia, South Australia, South Carolina, South Dakota, South European Russi, South Georgia, Spain, Sri Lanka, Sudan, Sulawesi, Sumatera, Svalbard, Sweden, Switzerland, Tadzhikistan, Taiwan, Tanzania, Tasmania, Tennessee, Texas, Thailand, Tibet, Transcaucasus, Tristan da Cunha, Tunisia, Turkey, Tuva, Uganda, Ukraine, Uruguay, Utah, Uzbekistan, Venezuela, Vermont, Victoria, Vietnam, Virginia, Washington, West Himalaya, West Siberia, West Virginia, Wisconsin, Wyoming, Xinjiang, Yakutskiya, Yugoslavia, Yukon, Zaïre

Introduced into:

Ascension, Mauritius, New Caledonia, Northern Provinces, Réunion, Western Australia


Callitriche L. appears in other Kew resources:

Date Reference Identified As Barcode Type Status Has image?
Verdcourt, B. [5480], United Kingdom 54862.000 No
Verdcourt, B. [5479], United Kingdom 54863.000 No

First published in Sp. Pl.: 969 (1753)

Accepted by

  • (2021). epublication.
  • Govaerts, R. (1999). World Checklist of Seed Plants 3(1, 2a & 2b): 1-1532. MIM, Deurne.
  • Govaerts, R. (2003). World Checklist of Selected Plant Families Database in ACCESS: 1-216203. The Board of Trustees of the Royal Botanic Gardens, Kew.
  • Lansdown, R.V. (2006). Notes on the water-starworts (Callitriche) recorded in Europe. Watsonia 26: 105-120.
  • Lansdown, R.V. (2008). Water-starworths (Callitriche) of Europe. Botanical Society of the British Isles Handbook 11: 1-180.
  • Lansdown, R.V. (2009). Nomenclatural notes on Callitriche (Callitrichaceae) in North America. Novon 19: 364-369.


Flora of Tropical East Africa

  • Gen. Pl., ed. 5: 5 (1754)
  • O. Hedberg & I. Hedberg, Tropical African Callitriche, Biol. Skr. 54: 19–30 (2001)
  • Schotsman in B.J.B.B. 55: 291–296 (1985)
  • in Bull. Mus. Hist. Nat. Paris, ser 4, 10: 3–17 (1988)

  • Flora of Tropical East Africa

    Flora of Tropical East Africa

  • Herbarium Catalogue Specimens

  • Kew Backbone Distributions

    The International Plant Names Index and World Checklist of Selected Plant Families 2022. Published on the Internet at and
    © Copyright 2017 World Checklist of Selected Plant Families.

  • Kew Living Collection Database

    Common Names from Royal Botanic Gardens, Kew Living Collection

  • Kew Names and Taxonomic Backbone

    The International Plant Names Index and World Checklist of Selected Plant Families 2022. Published on the Internet at and
    © Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families.