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Ceratophyllum demersum

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Taxonomy [top]

Kingdom Phylum Class Order Family
PLANTAE TRACHEOPHYTA MAGNOLIOPSIDA NYMPHAEALES CERATOPHYLLACEAE

Scientific Name: Ceratophyllum demersum
Species Authority: L.
Common Name/s:
English Coontail, Hornwort, Rigid Hornwort
French Ceratophylle émergé, Cornifle Nageant, Cornille, Herbe à cornes
Taxonomic Notes:

Ceratophyllum is a complicated genus with a range of taxa named but inconsistently recognised. Cook (1970) states that the genus includes four polymorphic species, but in parts of Europe some of the morphological variants are recognised as species or at a subordinate level. Whilst at least in the west, C. demersum s.s. is so widespread and abundant that it is unlikely that taxonomic issues will affect its conservation or Red List assessment, inconsistent recording within the C. demersum complex is likely to affect the red list assessments of any subordinate taxa assessed.

Assessment Information [top]

Red List Category & Criteria: Least Concern ver 3.1
Year Published: 2011
Assessor/s: Zhuang, X.
Reviewer/s: Juffe Bignoli, D., Homsombath, K. & Nophasead, L.
Contributor/s:
Justification:
This species is listed as Least Concern as it is widespread with stable populations and does not face any major threats. It has been very widely introduced and is considered a serious weed.

Geographic Range [top]

Range Description: This species is a cosmopolitan and occurs from the Azores and Europe (Castroviejo et al. 1987, Preston and Croft 1997, Gardenfors 2010, WCSPF 2010) east through the Middle East and the Indian subcontinent to east and southeast Asia (Cook 1970). It occurs in Africa north and south of the Sahara including Madagascar, as well as Australasia and north, central and south America. It is apparently introduced in Mauritius, New Zealand and Hawaii (World Checklist of Selected Plant Families 2010). The species has been recorded along the Mekong River in Thailand, Lao PDR, Cambodia and Viet Nam.

In China (Flora of China; eFlora 2011) this species is widespread throughout the country; it has been recorded from a number of provinces (Anhui, Fujian, Guangdong, Guangxi, Guizhou, Hebei, Heilongjiang, Henan, Hubei, Hunan, Jiangsu, Jilin, Nei Mongol, Ningxia, Shaanxi, Shandong, Shanxi, Sichuan, Taiwan, Xinjiang, Xizang, Yunnan, Zhejiang), and expected to be reported from additional provinces.

Countries:
Native:
Albania; Andorra; Angola (Angola, Angola); Argentina; Australia (Coral Sea Is. Territory); Austria; Belarus; Belgium; Benin; Bosnia and Herzegovina; Botswana; Brazil; Bulgaria; Burundi; Cambodia; Cameroon; Canada (British Columbia, Ontario); Chad; Chile; China (Anhui, Fujian, Guangdong, Guangxi, Guizhou, Hebei, Henan, Hunan, Jiangsu, Jilin, Nei Mongol, Ningxia, Shaanxi, Shandong, Shanxi, Sichuan, Tibet [or Xizang], Xinjiang, Yunnan, Zhejiang); Congo, The Democratic Republic of the; Côte d'Ivoire; Croatia; Cuba; Czech Republic; Denmark; Egypt (Egypt (African part)); Eritrea; Estonia; Ethiopia; Finland; France (France (mainland)); Gabon; Germany; Ghana; Greece (Greece (mainland), Kriti); Guernsey; Guinea-Bissau; Honduras; Hungary; India; Indonesia (Jawa, Kalimantan, Maluku, Sulawesi, Sumatera); Iran, Islamic Republic of; Iraq; Ireland; Italy (Italy (mainland), Sardegna, Sicilia); Jamaica; Japan; Kenya; Lao People's Democratic Republic; Latvia; Liechtenstein; Lithuania; Luxembourg; Macedonia, the former Yugoslav Republic of; Madagascar; Malawi; Moldova; Montenegro; Morocco; Mozambique; Netherlands; Nicaragua; Nigeria; Norway; Papua New Guinea (North Solomons, Papua New Guinea (main island group)); Philippines; Poland; Portugal (Azores, Portugal (mainland)); Puerto Rico (Puerto Rico (main island)); Romania; Russian Federation (Central European Russia, East European Russia, Kaliningrad, Khabarovsk, Magadan, North European Russia, Northwest European Russia, Tuva, Yakutiya); Rwanda; Senegal; Serbia (Serbia); Slovakia; Slovenia; South Africa (KwaZulu-Natal); Spain (Baleares, Spain (mainland)); Sudan; Sweden; Switzerland; Taiwan, Province of China; Tanzania, United Republic of; Thailand; Togo; Trinidad and Tobago; Turkey (Turkey-in-Europe); Uganda; Ukraine (Ukraine (main part)); United Kingdom (Great Britain, Northern Ireland); United States (Alaska, Arizona, California, Colorado, Connecticut, Idaho, Illinois, Indiana, Iowa, Maine, Massachusetts, Michigan, Minnesota, Missouri, Montana, Nebraska, Nevada, New Hampshire, New Jersey, New Mexico, New York, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Dakota, Texas, Utah, Vermont, Washington, West Virginia, Wisconsin, Wyoming); Venezuela; Viet Nam; Yemen (North Yemen, South Yemen)
Range Map: Click here to open the map viewer and explore range.

Population [top]

Population:

There is no information on global populations although it is a widespread and common plant in freshwater habitats. It is common in the rivers and lakes in the areas south of Yangtze River in China.

Population Trend: Stable

Habitat and Ecology [top]

Habitat and Ecology:

This species typically occurs in nutrient-rich standing or very slow-moving waters. Its apparent capability to tolerate elevated anthropogenic nutrient levels means that it can become very abundant or even dominant to the exclusion of most other species in canals, gravel pits, reservoirs and urban lakes.

Systems: Freshwater

Threats [top]

Major Threat(s): There are no major threats to this species.

Conservation Actions [top]

Conservation Actions: There are no conservation measures in place or needed.
Citation: Zhuang, X. 2011. Ceratophyllum demersum. In: IUCN 2012. IUCN Red List of Threatened Species. Version 2012.2. <www.iucnredlist.org>. Downloaded on 23 May 2013.
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