Nykrur

**Nykrur** (fræðiheiti *Potamogeton*) eru fjölærar rótfastar vatnaplöntur. Stilkir vaxa í vatni upp frá vatnbotni, blöð sem eru undir vatni eru aflöng en flotblöð sem eru í vatnsyfirborði eru rúnnuð. Blómin eru tvíkynjuð og sitja á axi sem kemur upp úr vatninu. Nykrur lifa í ferskvatni og ísöltu vatni. Þær vaxa oft í þéttum og miklum breiðum og eru mikilvægar sem fæða og búsvæði fyrir mörg dýr.
Það getur verið erfitt að tegundagreina nykrur.

### Listi yfir ''Potamogeton'' tegundir
Eftirfarandi listi er byggður á nýlegum skráningum The Plant List .

**[[Potamogeton acutifolius|P.&nbsp;acutifolius]]* Link ex Roem. & Schult. 1818 - Spjótnykra
**[[Potamogeton alpinus|P.&nbsp;alpinus]]* Balb. 1804 - Fjallnykra
**[[Potamogeton amplifolius|P.&nbsp;amplifolius]]* Tuck. 1848
**[[Potamogeton antaicus|P.&nbsp;antaicus]]* Hagstr. 1916
**[[Potamogeton australiensis|P.&nbsp;australiensis]]* A.Benn. 1910
**[[Potamogeton berchtoldii|P.&nbsp;berchtoldii]]* Fieber 1838 - Smánykra
**[[Potamogeton bicupulatus|P.&nbsp;bicupulatus]]* Fernald 1932
**[[Potamogeton biformis|P.&nbsp;biformis]]* Hagstr. 1916
**[[Potamogeton brasiliensis|P.&nbsp;brasiliensis]]* A.Benn. 1910
**[[Potamogeton chamissoi|P.&nbsp;chamissoi]]* A.Benn. 1904
**[[Potamogeton cheesemanii|P.&nbsp;cheesemanii]]* A.Benn. 1883
**[[Potamogeton chongyangensis|P.&nbsp;chongyangensis]]* W.X.Wang 1984
**[[Potamogeton coloratus|P.&nbsp;coloratus]]* Hornem. 1813 - Lindanykra
**[[Potamogeton compressus|P.&nbsp;compressus]]* L. 1753 - Sverðnykra
**[[Potamogeton confervoides|P.&nbsp;confervoides]]* Rchb. 1845
**[[Potamogeton crispus|P.&nbsp;crispus]]* L. 1753 - Hrukkunykra
**[[Potamogeton cristatus|P.&nbsp;cristatus]]* Regel & Maack, 1861
**[[Potamogeton delavayi|P.&nbsp;delavayi]]* A.Benn. 1892
**[[Potamogeton distinctus|P.&nbsp;distinctus]]* A. Benn. 1904
**[[Potamogeton diversifolius|P.&nbsp;diversifolius]]* Raf. 1811
**[[Potamogeton drummondii|P.&nbsp;drummondii]]* Benth. 1878
**[[Potamogeton epihydrus|P.&nbsp;epihydrus]]* Raf. 1811 - Bandnykra
**[[Potamogeton ferrugineus|P.&nbsp;ferrugineus]]* Hagstr. 1916
**[[Potamogeton floridanus|P.&nbsp;floridanus]]* Small 1903
**[[Potamogeton foliosus|P.&nbsp;foliosus]]* Raf. 1811
**[[Potamogeton fontigenus|P.&nbsp;fontigenus]]* Y.H.Guo, X.Z.Sun & H.Q.Wang 1985
**[[Potamogeton friesii|P.&nbsp;friesii]]* Rupr. 1845 - Broddnykra
**[[Potamogeton fryeri|P.&nbsp;fryeri]]* A.Benn. 1907
**[[Potamogeton gayi|P.&nbsp;gayi]]* A.Benn. 1892
**[[Potamogeton gramineus|P.&nbsp;gramineus]]* L. 1753 - Grasnykra
**[[Potamogeton heterocaulis|P.&nbsp;heterocaulis]]* Z.S.Diao 1994
**[[Potamogeton hillii|P.&nbsp;hillii]]* Morong 1881
**[[Potamogeton hoggarensis|P.&nbsp;hoggarensis]]* Dandy 1937
**[[Potamogeton illinoensis|P.&nbsp;illinoensis]]* Morong 1880
**[[Potamogeton intortusifolius|P.&nbsp;intortusifolius]]* J.B.He, L.Y.Zhou & H.Q.Wang 1988
**[[Potamogeton iriomotensis|P.&nbsp;iriomotensis]]* Masam. 1934
**[[Potamogeton juzepczukii|P.&nbsp;juzepczukii]]* P.I.Dorof. & Tzvelev 1983
**[[Potamogeton kashiensis|P.&nbsp;kashiensis]]* Z.S.Diao 1995
**[[Potamogeton lacunatifolius|P.&nbsp;lacunatifolius]]* Papch. 2001
**[[Potamogeton linguatus|P.&nbsp;linguatus]]* Hagstr. 1901
**[[Potamogeton lucens|P.&nbsp;lucens]]* L. 1753 - Gljánykra
**[[Potamogeton maackianus|P.&nbsp;maackianus]]* A.Benn. 1904
**[[Potamogeton mandschuriensis|P.&nbsp;mandschuriensis]]* (A.Benn.) A.Benn. 1924
**[[Potamogeton marianensis|P.&nbsp;marianensis]]* Cham. & Schltdl. 1827
**[[Potamogeton montevidensis|P.&nbsp;montevidensis]]* A.Benn. 1892
**[[Potamogeton nanus|P.&nbsp;nanus]]* Y.D.Chen 1987
**[[Potamogeton natans|P.&nbsp;natans]]* L. 1753 - Blöðrunykra
**[[Potamogeton nodosus|P.&nbsp;nodosus]]* Poir. 1816
**[[Potamogeton nomotoensis|P.&nbsp;nomotoensis]]* Kadono & T.Nog. 1991
**[[Potamogeton oakesianus|P.&nbsp;oakesianus]]* J.W.Robbins 1867
**[[Potamogeton obtusifolius|P.&nbsp;obtusifolius]]* Mert. & W.D.J.Koch 1823 - Pollanykra
**[[Potamogeton ochreatus|P.&nbsp;ochreatus]]* Raoul 1844
**[[Potamogeton octandrus|P.&nbsp;octandrus]]* Poir. 1816
**[[Potamogeton ogdenii|P.&nbsp;ogdenii]]* Hellq. & R.L.Hilton 1983
**[[Potamogeton oxyphyllus|P.&nbsp;oxyphyllus]]* Miq. 1867
**[[Potamogeton papuanicus|P.&nbsp;papuanicus]]* G.Wiegleb 1993
**[[Potamogeton paramoanus|P.&nbsp;paramoanus]]* R.R.Haynes & Holm-Niels. 1982
**[[Potamogeton parmatus|P.&nbsp;parmatus]]* Hagstr. 1908
**[[Potamogeton perfoliatus|P.&nbsp;perfoliatus]]* L. 1753 - Hjartanykra
**[[Potamogeton polygonifolius|P.&nbsp;polygonifolius]]* Pourr. 1788 - Rauðnykra
**[[Potamogeton polygonus|P.&nbsp;polygonus]]* Cham. & Schltdl. 1827
**[[Potamogeton praelongus|P.&nbsp;praelongus]]* Wulfen 1805 - Langnykra
**[[Potamogeton pulcher|P.&nbsp;pulcher]]* Tuck. 1843
**[[Potamogeton punense|P.&nbsp;punense]]* A.Galán 1988
**[[Potamogeton pusillus|P.&nbsp;pusillus]]* L. 1753 - Dvergnykra
**[[Potamogeton quinquenervius|P.&nbsp;quinquenervius]]* Hagstr. 1916
**[[Potamogeton reniacoensis|P.&nbsp;reniacoensis]]* Sparre 1956
**[[Potamogeton richardii|P.&nbsp;richardii]]* Solms 1867
**[[Potamogeton richardsonii|P.&nbsp;richardsonii]]* (A.Benn.) Rydb. 1905
**[[Potamogeton robbinsii|P.&nbsp;robbinsii]]* Oakes 1841
**[[Potamogeton rutilus|P.&nbsp;rutilus]]* Wolfg. 1827 Shetlandsnykra (líklega rangnefni)
**[[Potamogeton sarmaticus|P.&nbsp;sarmaticus]]* Mäemets 1978 publ. 1979
**[[Potamogeton schweinfurthii|P.&nbsp;schweinfurthii]]* A.Benn. 1901
**[[Potamogeton sclerocarpus|P.&nbsp;sclerocarpus]]* K.Schum. 1894
**[[Potamogeton sibiricus|P.&nbsp;sibiricus]]* A.Benn. 1890
**[[Potamogeton skvortsovii|P.&nbsp;skvortsovii]]* Klinkova 1993
**[[Potamogeton solomonensis|P.&nbsp;solomonensis]]* G.Wiegleb 1993
**[[Potamogeton spathuliformis|P.&nbsp;spathuliformis]]* (J.W.Robbins) Morong 1893
**[[Potamogeton spirilliformis|P.&nbsp;spirilliformis]]* Hagstr. 1916
**[[Potamogeton spirillus|P.&nbsp;spirillus]]* Tuck. 1848
**[[Potamogeton stenostachys|P.&nbsp;stenostachys]]* K.Schum. 1894
**[[Potamogeton strictifolius|P.&nbsp;strictifolius]]* A.Benn. 1902
**[[Potamogeton subnitens|P.&nbsp;subnitens]]* Hagstr. 1916
**[[Potamogeton suboblongus|P.&nbsp;suboblongus]]* Hagstr. 1916
**[[Potamogeton sumatranus|P.&nbsp;sumatranus]]* Miq. 1861
**[[Potamogeton tennesseensis|P.&nbsp;tennesseensis]]* Fernald 1936
**[[Potamogeton tepperi|P.&nbsp;tepperi]]* A.Benn. 1887
**[[Potamogeton tricarinatus|P.&nbsp;tricarinatus]]* F.Muell. & A.Benn. 1892
**[[Potamogeton trichoides|P.&nbsp;trichoides]]* Cham. & Schltdl. 1827 - Hárnykra
**[[Potamogeton tubulatus|P.&nbsp;tubulatus]]* Hagstr. 1922
**[[Potamogeton ulei|P.&nbsp;ulei]]* K.Schum. 1894
**[[Potamogeton uruguayensis|P.&nbsp;uruguayensis]]* A.Benn. & Graebn.
**[[Potamogeton vaseyi|P.&nbsp;vaseyi]]* J.W.Robbins 1867
**[[Potamogeton wrightii|P.&nbsp;wrightii]]* Morong 1886

### Listi yfir ''Potamogeton'' blendinga

**[[Potamogeton × anguillanus|P.&nbsp;×&nbsp;anguillanus]]* Koidz.
**[[Potamogeton × angustifolius|P.&nbsp;×&nbsp;angustifolius]]* J.Presl
**[[Potamogeton × apertus|P.&nbsp;×&nbsp;apertus]]* Miki
**[[Potamogeton × argutulus|P.&nbsp;×&nbsp;argutulus]]* Hagstr.
**[[Potamogeton × attenuatus|P.&nbsp;×&nbsp;attenuatus]]* Hagstr.
**[[Potamogeton × babingtonii|P.&nbsp;×&nbsp;babingtonii]]* A.Benn.
**[[Potamogeton × billupsii|P.&nbsp;×&nbsp;billupsii]]* Fryer
**[[Potamogeton × cadburyae|P.&nbsp;×&nbsp;cadburyae]]* Dandy & G.Taylor
**[[Potamogeton × cognatus|P.&nbsp;×&nbsp;cognatus]]* Asch. & Graebn.
**[[Potamogeton × cooperi|P.&nbsp;×&nbsp;cooperi]]* (Fryer) Fryer
**[[Potamogeton × faurei|P.&nbsp;×&nbsp;faurei]]* (A.Benn.) Miki
**[[Potamogeton × fluitans|P.&nbsp;×&nbsp;fluitans]]* Roth - Hnútanykra
**[[Potamogeton × franconicus|P.&nbsp;×&nbsp;franconicus]]* G.Fisch.
**[[Potamogeton × gessnacensis|P.&nbsp;×&nbsp;gessnacensis]]* G.Fisch.
**[[Potamogeton × griffithii|P.&nbsp;×&nbsp;griffithii]]* A.Benn.
**[[Potamogeton × grovesii|P.&nbsp;×&nbsp;grovesii]]* Dandy & G.Taylor
**[[Potamogeton × haynesii|P.&nbsp;×&nbsp;haynesii]]* Hellq. & G.E.Crow
**[[Potamogeton × inbaensis|P.&nbsp;×&nbsp;inbaensis]]* Kadono
**[[Potamogeton × kamogawaensis|P.&nbsp;×&nbsp;kamogawaensis]]* Miki
**[[Potamogeton × kyushuensis|P.&nbsp;×&nbsp;kyushuensis]]* Kadono & Wiegleb
**[[Potamogeton × lanceolatifolius|P.&nbsp;×&nbsp;lanceolatifolius]]* (Tiselius) C.D.Preston
**[[Potamogeton × lanceolatus|P.&nbsp;×&nbsp;lanceolatus]]* Sm.
**[[Potamogeton × leptocephalus|P.&nbsp;×&nbsp;leptocephalus]]* Koidz.
**[[Potamogeton × lintonii|P.&nbsp;×&nbsp;lintonii]]* Fryer
**[[Potamogeton × malainoides|P.&nbsp;×&nbsp;malainoides]]* Miki
**[[Potamogeton × mariensis|P.&nbsp;×&nbsp;mariensis]]* Papch.
**[[Potamogeton × mysticus|P.&nbsp;×&nbsp;mysticus]]* Morong
**[[Potamogeton × nericius|P.&nbsp;×&nbsp;nericius]]* Hagstr.
**[[Potamogeton × nerviger|P.&nbsp;×&nbsp;nerviger]]* Wolfg.
**[[Potamogeton × nitens|P.&nbsp;×&nbsp;nitens]]* Weber
**[[Potamogeton × olivaceus|P.&nbsp;×&nbsp;olivaceus]]* Baagøe ex G.Fisch.
**[[Potamogeton × orientalis|P.&nbsp;×&nbsp;orientalis]]* Hagstr.
**[[Potamogeton × philippinensis|P.&nbsp;×&nbsp;philippinensis]]* A.Benn.
**[[Potamogeton × prussicus|P.&nbsp;×&nbsp;prussicus]]* Hagstr.
**[[Potamogeton × pseudofriesii|P.&nbsp;×&nbsp;pseudofriesii]]* Dandy & G.Taylor
**[[Potamogeton × rectifolius|P.&nbsp;×&nbsp;rectifolius]]* A.Benn.
**[[Potamogeton × salicifolius|P.&nbsp;×&nbsp;salicifolius]]* Wolfg.
**[[Potamogeton × schreberi|P.&nbsp;×&nbsp;schreberi]]* G.Fisch.
**[[Potamogeton × scoliophyllus|P.&nbsp;×&nbsp;scoliophyllus]]* Hagstr.
**[[Potamogeton × sparganiifolius|P.&nbsp;×&nbsp;sparganiifolius]]* Laest. ex Fr.
**[[Potamogeton × spathulatus|P.&nbsp;×&nbsp;spathulatus]]* Schrad. ex W.D.J.Koch & Ziz
**[[Potamogeton × subsessilis|P.&nbsp;×&nbsp;subsessilis]]* Hagstr.
**[[Potamogeton × sudermanicus|P.&nbsp;×&nbsp;sudermanicus]]* Hagstr.
**[[Potamogeton × undulatus|P.&nbsp;×&nbsp;undulatus]]* Wolfg.
**[[Potamogeton × vaginans|P.&nbsp;×&nbsp;vaginans]]* (Bojer ex A.Benn.) Hagstr.
**[[Potamogeton × varians|P.&nbsp;×&nbsp;varians]]* Morong
**[[Potamogeton × variifolius|P.&nbsp;×&nbsp;variifolius]]* Thore
**[[Potamogeton × vepsicus|P.&nbsp;×&nbsp;vepsicus]]* A.A.Bobrov & Chemeris

## Tilvísanir