Potamogeton octandrusPoir.

WFO wfo-0000769927 Accepted WFO 2026-06 8 photographs CC0 / CC BY / CC BY-SA

Plate 1 figs. a–h · 4 observations

This species has been photographed under an open licence only 4 times, so some figures below are different views of the same plant, taken on the same day, rather than different individuals. They are usually different parts of it: the leaf, the flower, the bark.

Potamogeton octandrus, photographed by chiuluan
fig. a chiuluan, CC BY 4.0 / 2022-04-09 / obs. 187475532
Potamogeton octandrus, photographed by Tony Eales
fig. b Tony Eales, CC BY-SA 4.0 / obs. 159551424
Potamogeton octandrus, photographed by Jacy Chen
fig. c Jacy Chen, CC BY 4.0 / obs. 154939735
Potamogeton octandrus, photographed by Richard Fuller
fig. d Richard Fuller, CC0 1.0 / obs. 59074840
Potamogeton octandrus, photographed by chiuluan
fig. e chiuluan, CC BY 4.0 / obs. 187475534
Potamogeton octandrus, photographed by Tony Eales
fig. f Tony Eales, CC BY-SA 4.0 / obs. 159551593
Potamogeton octandrus, photographed by chiuluan
fig. g chiuluan, CC BY 4.0 / obs. 187475538
Potamogeton octandrus, photographed by chiuluan
fig. h chiuluan, CC BY 4.0 / obs. 187475535

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 23 botanical countries

Regions where Potamogeton octandrus is native: Amur, China North-Central, China South-Central, China Southeast, Hainan, Inner Mongolia, Japan, Khabarovsk, Korea, Manchuria, Nansei-shoto, Primorye, Taiwan, Assam, Bangladesh, East Himalaya, India, Jawa, Myanmar, Nepal, Thailand, Vietnam, West Himalaya AmurChina North-CentralChina South-CentralChina SoutheastHainanInner MongoliaJapanKhabarovskManchuriaPrimoryeTaiwanAssamBangladeshEast HimalayaIndiaJawaMyanmarNepalThailandVietnamWest Himalaya KoreaNansei-shoto
Native distribution of Potamogeton octandrus, 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
Amur AMU ASIA-TEMPERATE
China North-Central CHN
China South-Central CHC
China Southeast CHS
Hainan CHH
Inner Mongolia CHI
Japan JAP
Khabarovsk KHA
Korea KOR
Manchuria CHM
Nansei-shoto NNS
Primorye PRM
Taiwan TAI
Assam ASS ASIA-TROPICAL
Bangladesh BAN
East Himalaya EHM
India IND
Jawa JAW
Myanmar MYA
Nepal NEP
Thailand THA
Vietnam VIE
West Himalaya WHM

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 75 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -7.5 °C 10.8 °C 14.4 °C
Warmest month, mean daily high 22.7 °C 28.0 °C 30.4 °C
Annual rainfall 829 mm 1,928 mm 4,891 mm
Rainfall in the driest quarter 44 mm 200 mm 827 mm

It is found where winters bring hard 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 75 research-grade observations of Potamogeton octandrus 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 14 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.

  • Hydrogeton heterophyllum Lour.
  • Potamogeton asiaticus A.Benn.
  • Potamogeton hubeiensis W.X.Wang, X.Z.Sun & H.Q.Wang
  • Potamogeton iriomotensis Masam.
  • Potamogeton limosellifolius Maxim. ex Korsh.
  • Potamogeton miduhikimo Makino ex A.Benn.
  • Potamogeton mizuhikimo Makino
  • Potamogeton numasakianus A.Benn.
  • Potamogeton octandrus subsp. limosellifolius (Maxim. ex Korsh.) Vorosch.
  • Potamogeton octandrus var. asiaticus (A.Benn.) Tzvelev
  • Potamogeton octandrus var. limosellifolius (Maxim. ex Korsh.) Tzvelev
  • Potamogeton octandrus var. minduhikimo (Makino) H.Hara
  • Potamogeton octandrus var. mizuhikimo (Makino) H.Hara
  • Potamogeton subfuscus A.Benn.

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. 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.