''Najas'', the water-nymphs or naiads, is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

aquatic plant Aquatic plants are plants that have adapted to living in aquatic environments (saltwater or freshwater). They are also referred to as hydrophytes or macrophytes to distinguish them from algae and other microphytes. A macrophyte is a plant that ...

s. It is

cosmopolitan Cosmopolitan may refer to: Food and drink * Cosmopolitan (cocktail), also known as a "Cosmo" History * Rootless cosmopolitan, a Soviet derogatory epithet during Joseph Stalin's anti-Semitic campaign of 1949–1953 Hotels and resorts * Cosmopoli ...

in distribution, first described for modern science by

Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the ...

in 1753. Until 1997, it was rarely placed in the

Hydrocharitaceae Hydrocharitaceae is a flowering plant family including 16 known genera with a total of ca 135 known species (Christenhusz & Byng 2016), that including a number of species of aquatic plant, for instance the tape-grasses, the well known Canadia ...

,Angiosperm Phylogeny Group (2003). "An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG II". ''Botanical Journal of the Linnean Society'' 141(4): 399-436. (Available online
Abstract

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and was often taken as constituting (by itself) the family Najadaceae.197. Najadaceae A. L. de Jussieu
''

Flora of North America The ''Flora of North America North of Mexico'' (usually referred to as ''FNA'') is a multivolume work describing the native plants and naturalized plants of North America, including the United States, Canada, St. Pierre and Miquelon, and Greenla ...

'' The

APG II system The APG II system (Angiosperm Phylogeny Group II system) of plant classification is the second, now obsolete, version of a modern, mostly molecular-based, system of plant taxonomy that was published in April 2003 by the Angiosperm Phylogeny Gr ...

, of 2003 (unchanged from the

APG system The APG system (Angiosperm Phylogeny Group system) of plant classification is the first version of a modern, mostly molecular-based, system of plant taxonomy. Published in 1998 by the Angiosperm Phylogeny Group, it was replaced by the improved AP ...

, of 1998), places the genus in family

, in the order

Alismatales The Alismatales (alismatids) are an order of flowering plants including about 4,500 species. Plants assigned to this order are mostly tropical or aquatic. Some grow in fresh water, some in marine habitats. Description The Alismatales compri ...

of the

monocots Monocotyledons (), commonly referred to as monocots, (Lilianae ''sensu'' Chase & Reveal) are grass and grass-like flowering plants (angiosperms), the seeds of which typically contain only one embryonic leaf, or cotyledon. They constitute one of t ...

. An infrageneric classification of two sections is proposed: Section ''Americanae'' and sect. ''Caulinia''.Ito, Y., Nr. Tanaka, S.W. Gale, O. Yano, J. Li (2017) "Phylogeny of Najas (Hydrocharitaceae) revisited: Implications for systematics and evolution". ''Taxon'' 66(2): 309-323
doi: 10.12705/662.2
/ref> ;Species # '' Najas affinis'' Rendle - South America, Senegal, Guinea-Bissau # '' Najas ancistrocarpa'' A.Braun ex Magnus - China, Japan, Taiwan # '' Najas arguta'' Kunth - Cuba, Costa Rica, Panama, South America # '' Najas australis'' Bory ex Rendle - India, Madagascar, Mauritius, KwaZulu-Natal, Seychelles # '' Najas baldwinii'' Horn - West Africa # ''

Najas brevistyla ''Najas'', the water-nymphs or naiads, is a genus of aquatic plants. It is cosmopolitan in distribution, first described for modern science by Linnaeus in 1753. Until 1997, it was rarely placed in the Hydrocharitaceae,Angiosperm Phylogeny Grou ...

'' Rendle - Assam # '' Najas browniana'' Rendle - southern China, India, Taiwan, Java, Cavern Island in Northern Territory of Australia # ''

Najas chinensis ''Najas'', the water-nymphs or naiads, is a genus of aquatic plants. It is cosmopolitan in distribution, first described for modern science by Linnaeus in 1753. Until 1997, it was rarely placed in the Hydrocharitaceae,Angiosperm Phylogeny Gro ...

'' N.Z.Wang - Primorye, China, Taiwan, Japan # '' Najas conferta'' (A.Braun) A.Braun - Cuba, Hispaniola, Panama, Brazil # '' Najas faveolata'' A. Br. ex Magnus # '' Najas filifolia'' R.R.Haynes - southeastern United States (Georgia, Alabama, Florida) # ''

Najas flexilis ''Najas flexilis'' is an aquatic annual plant native to parts of North America and Europe. It is native to northern and central Europe from Norway to Ireland to Switzerland, and from there across Russia (including Siberia). It is also considered ...

'' (Willd.) Rostk. & W.L.E. Schmidt (1824) - temperate Northern Hemisphere # '' Najas gracillima'' (A.Braun ex Engelm.) Magnus - Asia, North America # ''

Najas graminea ''Najas graminea'', also known as ricefield water-nymph is a species of aquatic plant found in freshwater habitats, especially still or slow-moving waters, like ponds and rice fields. It grows to a maximum length of 30 cm. The flowers are mo ...

'' Delile (1813) - Africa, Asia, New Guinea, Melanesia, northern Australia; naturalized in California and parts of Europe # ''

Najas grossareolata ''Najas grossareolata'', called the Sri Lankan water nymph, is an aquatic plant growing in fresh water ponds. It is a rare and little-known species known from Sri Lanka Sri Lanka (, ; si, ශ්‍රී ලංකා, Śrī Laṅkā, t ...

'' L.Triest - Sri Lanka # ''

Najas guadalupensis ''Najas guadalupensis'' is a species of aquatic plant known by the common names southern waternymph, guppy grass, najas grass, and common water nymph. It is native to the Americas, where it is widespread. It is considered native to Canada (from A ...

'' (Spreng.) Magnus - North and South America, Caribbean # ''

Najas hagerupii ''Najas hagerupii'', called the West African water nymph, is an aquatic plant growing in fresh water rivers and ponds. It is a rare and little-known species known only from the West African nations of Ghana and Mali Mali (; ), officially t ...

'' Horn - Ghana, Mali # ''

Najas halophila ''Najas halophila'' is an aquatic plant species native to Java, New Guinea and Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = C ...

'' L.Triest - Java, New Guinea, Queensland # ''

Najas heteromorpha ''Najas'', the water-nymphs or naiads, is a genus of aquatic plants. It is cosmopolitan in distribution, first described for modern science by Linnaeus in 1753. Until 1997, it was rarely placed in the Hydrocharitaceae,Angiosperm Phylogeny Gro ...

'' Griff. ex Voigt - eastern India # ''

Najas horrida ''Najas'', the water-nymphs or naiads, is a genus of aquatic plants. It is cosmopolitan in distribution, first described for modern science by Linnaeus in 1753. Until 1997, it was rarely placed in the Hydrocharitaceae,Angiosperm Phylogeny Gro ...

'' A.Braun ex Magnus - Africa, Madagascar, Sinai # ''

Najas indica ''Najas indica'' is a species of aquatic plant found in freshwater habitats, especially still or slow-moving waters, like ponds and rice fields. The flowers are monoecious. Distribution The natural distribution of this annual plant is India, Chi ...

'' (Willd.) Cham. (1829) - Indian Subcontinent, China, Southeast Asia, New Guinea # '' Najas kurziana '' Rendle - Bihar, East Timor # '' Najas madagascariensis'' Rendle - Madagascar; naturalized in Mauritius # '' Najas malesiana'' W.J.de Wilde - India, Bangladesh, Indochina, Malaysia, Indonesia, Philippines; naturalized in eastern Brazil # ''

Najas marina ''Najas marina'' is a species of aquatic plant known by the common names spiny water nymph, spiny naiad and holly-leaved naiad. It is an extremely widespread species, reported across Europe, Asia, Africa, Australia, the Americas and many oceani ...

'' L. (1753) - widespread and nearly cosmopolitan # ''

Najas minor ''Najas minor'', known as brittle naiad or brittle waternymph, is an annual aquatic plant, a submersed herb. It is native to Europe, Asia and North Africa from the Netherlands to Morocco east to Japan and the Philippines, including China, Siberia ...

'' All. (1773) - widespread in Europe, Asia, Africa; naturalized in eastern North America # '' Najas oguraensis'' Miki - East Asia, Himalayas (Pakistan, Nepal, northern India) # '' Najas pectinata'' (Parl.) Magnus - Sahara # '' Najas pseudogracillima'' L.Triest - Hong Kong # '' Najas rigida'' Griff. - eastern India # ''

Najas schweinfurthii ''Najas'', the water-nymphs or naiads, is a genus of aquatic plants. It is cosmopolitan (distribution), cosmopolitan in distribution, first described for modern science by Carl Linnaeus, Linnaeus in 1753. Until 1997, it was rarely placed in th ...

'' Magnus - Senegal, Cameroon, Ethiopia, Sudan, Tanzania # '' Najas tenuicaulis'' Miki - Honshu Island in Japan # '' Najas tenuifolia'' R.Br. - Hong Kong, Southeast Asia, Australia # '' Najas tenuis'' Magnus – India, Sri Lanka, Myanmar # '' Najas tenuissima'' (A.Braun ex Magnus) Magnus - Finland, Russia, Hokkaido # '' Najas testui'' Rendle - western + central Africa # '' Najas welwitschii'' Rendle - tropical Africa, western India # '' Najas wrightiana'' A.Braun - Mexico, Central America, Cuba, Bahamas, Venezuela; naturalized in Florida

References

External links

Najadaceae
in L. Watson and M.J. Dallwitz (1992 onwards
''The families of flowering plants
: descriptions, illustrations, identification, information retrieval.'' Version: 9 March 2006. http://delta-intkey.com .

Flavon's art gallery
Najadaceae of Mongolia in FloraGREIF
{{Taxonbar, from=Q159215 Aquatic plants Hydrocharitaceae genera Taxa named by Carl Linnaeus