Isolepis fluitans(L.) R.Br.

Floating Club-rush

WFO wfo-0000448873 Accepted WFO 2026-06 8 photographs CC BY / CC BY-SA

Plate 1 figs. a–h · 8 separate observations

Isolepis fluitans, photographed by Victoria Benstead-Hume
fig. a Victoria Benstead-Hume, CC BY 4.0 / 2022-05-31 / obs. 202243739
Isolepis fluitans, photographed by Augustin Soulard
fig. b Augustin Soulard, CC BY 4.0 / obs. 201780376
Isolepis fluitans, photographed by Andre Hosper
fig. c Andre Hosper, CC BY 4.0 / obs. 147800336
Isolepis fluitans, photographed by Andre Hosper
fig. d Andre Hosper, CC BY 4.0 / obs. 147799955
Isolepis fluitans, photographed by Andre Hosper
fig. e Andre Hosper, CC BY 4.0 / obs. 130247082
Isolepis fluitans, photographed by Tony Rebelo
fig. f Tony Rebelo, CC BY-SA 4.0 / obs. 113725563
Isolepis fluitans, photographed by Dan Wrench
fig. g Dan Wrench, CC BY 4.0 / obs. 158630273
Isolepis fluitans, photographed by Andre Hosper
fig. h Andre Hosper, CC BY 4.0 / obs. 185856692

Every figure is a research-grade observation under CC0, CC BY or CC BY-SA, rehosted with the photographer’s name, the licence and the observation it came from. Photographs under a NonCommercial licence are excluded from this site and are never stored, which costs us a great many pictures and is not negotiable.

Native range 55 botanical countries

Regions where Isolepis fluitans is native: Angola, Azores, Burundi, Cameroon, Cape Provinces, Comoros, DR Congo, Eritrea, Eswatini, Ethiopia, Free State, Kenya, KwaZulu-Natal, Lesotho, Madagascar, Malawi, Mali, Mozambique, Namibia, Nigeria, Northern Provinces, Réunion, Rwanda, Sudan-South Sudan, Tanzania, Uganda, Zambia, Zimbabwe, Assam, India, Jawa, Sri Lanka, Vietnam, New South Wales, New Zealand North, New Zealand South, Queensland, South Australia, Tasmania, Victoria, Western Australia, Belgium, Czechia-Slovakia, Denmark, France, Germany, Great Britain, Ireland, Italy, Netherlands, Norway, Poland, Portugal, Spain, Sweden AngolaBurundiCameroonCape ProvincesDR CongoEritreaEswatiniEthiopiaFree StateKenyaKwaZulu-NatalLesothoMadagascarMalawiMaliMozambiqueNamibiaNigeriaNorthern ProvincesRwandaSudan-South SudanTanzaniaUgandaZambiaZimbabweAssamIndiaJawaSri LankaVietnamNew South WalesNew Zealand NorthNew Zealand SouthQueenslandSouth AustraliaTasmaniaVictoriaWestern AustraliaBelgiumCzechia-SlovakiaDenmarkFranceGermanyIrelandItalyNetherlandsNorwayPolandPortugalSpainSweden AzoresComorosRéunion
Native distribution of Isolepis fluitans, after Kew’s World Checklist of Vascular Plants. Introduced, extinct and doubtful records are excluded, so this is where the plant is from, not everywhere it now grows. Regions too small to draw at this scale are marked with a dot.
RegionTDWG codeContinent
Angola ANG AFRICA
Azores AZO
Burundi BUR
Cameroon CMN
Cape Provinces CPP
Comoros COM
DR Congo ZAI
Eritrea ERI
Eswatini SWZ
Ethiopia ETH
Free State OFS
Kenya KEN
KwaZulu-Natal NAT
Lesotho LES
Madagascar MDG
Malawi MLW
Mali MLI
Mozambique MOZ
Namibia NAM
Nigeria NGA
Northern Provinces TVL
Réunion REU
Rwanda RWA
Sudan-South Sudan SUD
Tanzania TAN
Uganda UGA
Zambia ZAM
Zimbabwe ZIM
Belgium BGM EUROPE
Czechia-Slovakia CZE
Denmark DEN
France FRA
Germany GER
Great Britain GRB
Ireland IRE
Italy ITA
Netherlands NET
Norway NOR
Poland POL
Portugal POR
Spain SPA
Sweden SWE
New South Wales NSW AUSTRALASIA
New Zealand North NZN
New Zealand South NZS
Queensland QLD
South Australia SOA
Tasmania TAS
Victoria VIC
Western Australia WAU
Assam ASS ASIA-TROPICAL
India IND
Jawa JAW
Sri Lanka SRL
Vietnam VIE

Not drawn on the map: Great Britain. We hold no public-domain boundary for this region, so it is listed rather than guessed at.

Region boundaries approximated from Natural Earth (public domain) and mapped to TDWG World Geographical Scheme for Recording Plant Distributions (WGSRPD) level-3 botanical countries (Brummitt 2001). Indicative, not the official WGSRPD geometry.

Where it actually grows measured, from 224 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -0.8 °C 3.4 °C 10.6 °C
Warmest month, mean daily high 15.7 °C 22.0 °C 26.9 °C
Annual rainfall 703 mm 959 mm 2,512 mm
Rainfall in the driest quarter 37 mm 161 mm 315 mm

It is found where winters bring light frost. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 224 research-grade observations of Isolepis fluitans that carry a coordinate, and this is the range those places actually span. The 5th and 95th percentiles are used rather than the minimum and maximum, because a single cultivated specimen in a heated conservatory should not widen a tropical plant's range to the Arctic.

This is not a hardiness zone. A USDA zone is the average annual extreme minimum temperature. The figure above is the mean daily minimum of the coldest month, which is a different quantity and is typically far warmer. Reading one as the other would place a plant several zones too warm, so we do not publish a hardiness zone, because we do not have one.

Also published as 40 synonyms

A synonym is not an error. It is a record of botanists disagreeing, in print, about where this plant belongs. Each of these was somebody’s considered answer.

  • Clavula fluitans (L.) Dumort.
  • Cyperus fluitans (L.) Missbach & E.H.L.Krause
  • Dichostylis fluitans (L.) Rchb.
  • Eleocharis fluitans (L.) Hook.
  • Eleogiton curvula Nees
  • Eleogiton fascicularis Nees
  • Eleogiton fluitans (L.) Link
  • Eleogiton fluitans var. fasciculata Miq.
  • Heleogiton fluitans (L.) Link ex Rchb.
  • Isolepis curvata (Nees) Zoll.
  • Isolepis curvula (Nees) Kunth
  • Isolepis fascicularis (Nees) Kunth
  • Isolepis fluitans var. major Lye
  • Isolepis fluitans var. terrestris Hook.f.
  • Isolepis fuscescens Steud.
  • Isolepis giraudyi Steud.
  • Isolepis intricata Steud.
  • Isolepis inyangensis Muasya & Goetgh.
  • Isolepis lenticularis R.Br.
  • Isolepis nervosa Hochst. ex A.Rich.
  • Schoenoplectus fluitans (L.) Palla
  • Scirpidiella fluitans (L.) Rauschert
  • Scirpus amazonicus Beetle
  • Scirpus carsei Kük.

and 16 more.

Sourcesevery claim on this page

  1. World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
  2. iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
  3. Wikidata. common name (P1843), joined on the World Flora Online identifier (P7715). CC0. Retrieved 2026-07-13.
  4. Kew, World Checklist of Vascular Plants (WCVP v16). native distribution by TDWG level-3 botanical country, and life form. CC BY 3.0. Retrieved 2026-06-04.

We publish what we can source and we say so when we cannot. This page has no care advice and no toxicity claim, because we do not yet have those from a source we can cite.