Ruppia cirrhosa(Petagna) Grande

Species code: RcSpiral Ditchgrassspiral ditchgrassspiral tasselweed

WFO wfo-0000733703 Accepted WFO 2026-06 8 photographs CC BY

Plate 1 figs. a–h · 5 observations

This species has been photographed under an open licence only 5 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.

Ruppia cirrhosa, photographed by Duarte Frade
fig. a Duarte Frade, CC BY 4.0 / 2020-05-31 / obs. 79992525

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.

The specimen a real sheet, in a real collection

Herbarium
The New York Botanical Garden
Accession
1625737
Filed as
Ruppia cirrhosa (Petagna) Grande
Det. by
not recorded on this sheet
Collected
not recorded
Origin
not recorded
The sheet
View the digitised specimen (CC BY 4.0)

A real pressed plant, in a real collection, under the accession number above. Not an illustration of one. The holding institution does not serve this sheet’s image to third parties, so there is no photograph here. The record is real and the link goes to it. Where we hold no openly licensed sheet for a species this section is simply absent, and where a sheet never recorded who determined it, that field stays empty rather than being filled in. Roughly half of all herbarium sheets never recorded a determiner, which is ordinary.

Native range 98 botanical countries

Regions where Ruppia cirrhosa is native: Algeria, Cape Provinces, Egypt, KwaZulu-Natal, Libya, Morocco, Namibia, Tunisia, Altay, China North-Central, China Southeast, Cyprus, East Aegean Is., Iran, Japan, Kamchatka, Kazakhstan, Khabarovsk, Korea, Manchuria, North Caucasus, Palestine, Primorye, Sakhalin, Sinai, Transcaucasus, Türkiye, India, Jawa, Lesser Sunda Is., Albania, Baleares, Baltic States, Belarus, Belgium, Bulgaria, Central European Russia, Corse, Denmark, East European Russia, Finland, France, Germany, Great Britain, Greece, Ireland, Italy, Kriti, Krym, Netherlands, Northwest European Russia, Norway, NW. Balkan Pen., Poland, Portugal, Sardegna, Sicilia, South European Russia, Spain, Sweden, Ukraine, Alaska, Alberta, Aleutian Is., Arizona, British Columbia, California, Colorado, Illinois, Kansas, Manitoba, Mexico Northwest, Michigan, Minnesota, Missouri, Montana, Nebraska, Nevada, New Mexico, North Dakota, Northwest Territories, Ohio, Oklahoma, Oregon, Saskatchewan, South Dakota, Texas, Utah, Washington, Wisconsin, Wyoming, Yukon, Argentina Northeast, Argentina Northwest, Cayman Is., Jamaica, Leeward Is., Puerto Rico AlgeriaCape ProvincesEgyptKwaZulu-NatalLibyaMoroccoNamibiaTunisiaAltayChina North-CentralChina SoutheastCyprusEast Aegean Is.IranJapanKamchatkaKazakhstanKhabarovskManchuriaNorth CaucasusPalestinePrimoryeSakhalinSinaiTranscaucasusTürkiyeIndiaJawaLesser Sunda Is.AlbaniaBaltic StatesBelarusBelgiumBulgariaCentral European RussiaCorseDenmarkEast European RussiaFinlandFranceGermanyGreeceIrelandItalyKritiKrymNetherlandsNorthwest European RussiaNorwayNW. Balkan Pen.PolandPortugalSiciliaSouth European RussiaSpainSwedenUkraineAlaskaAlbertaArizonaBritish ColumbiaCaliforniaColoradoIllinoisKansasManitobaMexico NorthwestMichiganMinnesotaMissouriMontanaNebraskaNevadaNew MexicoNorth DakotaNorthwest TerritoriesOhioOklahomaOregonSaskatchewanSouth DakotaTexasUtahWashingtonWisconsinWyomingYukonArgentina NortheastArgentina NorthwestJamaicaPuerto Rico KoreaBalearesSardegnaCayman Is.Leeward Is.
Native distribution of Ruppia cirrhosa, 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
Albania ALB EUROPE
Baleares BAL
Baltic States BLT
Belarus BLR
Belgium BGM
Bulgaria BUL
Central European Russia RUC
Corse COR
Denmark DEN
East European Russia RUE
Finland FIN
France FRA
Germany GER
Great Britain GRB
Greece GRC
Ireland IRE
Italy ITA
Kriti KRI
Krym KRY
Netherlands NET
Northwest European Russia RUW
Norway NOR
NW. Balkan Pen. YUG
Poland POL
Portugal POR
Sardegna SAR
Sicilia SIC
South European Russia RUS
Spain SPA
Sweden SWE
Ukraine UKR
Alaska ASK NORTHERN AMERICA
Alberta ABT
Aleutian Is. ALU
Arizona ARI
British Columbia BRC
California CAL
Colorado COL
Illinois ILL
Kansas KAN
Manitoba MAN
Mexico Northwest MXN
Michigan MIC
Minnesota MIN
Missouri MSO
Montana MNT
Nebraska NEB
Nevada NEV
New Mexico NWM
North Dakota NDA
Northwest Territories NWT
Ohio OHI
Oklahoma OKL
Oregon ORE
Saskatchewan SAS
South Dakota SDA
Texas TEX
Utah UTA
Washington WAS
Wisconsin WIS
Wyoming WYO
Yukon YUK
Altay ALT ASIA-TEMPERATE
China North-Central CHN
China Southeast CHS
Cyprus CYP
East Aegean Is. EAI
Iran IRN
Japan JAP
Kamchatka KAM
Kazakhstan KAZ
Khabarovsk KHA
Korea KOR
Manchuria CHM
North Caucasus NCS
Palestine PAL
Primorye PRM
Sakhalin SAK
Sinai SIN
Transcaucasus TCS
Türkiye TUR
Algeria ALG AFRICA
Cape Provinces CPP
Egypt EGY
KwaZulu-Natal NAT
Libya LBY
Morocco MOR
Namibia NAM
Tunisia TUN
Argentina Northeast AGE SOUTHERN AMERICA
Argentina Northwest AGW
Cayman Is. CAY
Jamaica JAM
Leeward Is. LEE
Puerto Rico PUE
India IND ASIA-TROPICAL
Jawa JAW
Lesser Sunda Is. LSI

Not drawn on the map: Great Britain, Aleutian Is.. We hold no public-domain boundary for these regions, so they are 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 116 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -21.0 °C 5.8 °C 12.2 °C
Warmest month, mean daily high 18.4 °C 25.5 °C 29.6 °C
Annual rainfall 288 mm 616 mm 1,312 mm
Rainfall in the driest quarter 11 mm 50 mm 183 mm

It is found where winters are severely cold. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 116 research-grade observations of Ruppia cirrhosa 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 13 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.

  • Buccaferrea cirrhosa Petagna
  • Dzieduszyckia limnobis Rehmann
  • Ruppia cirrhosa subsp. occidentalis (S.Watson) Á.Löve & D.Löve
  • Ruppia cirrhosa var. truncatifolia (Miki) H.Hara
  • Ruppia lacustris Macoun
  • Ruppia maritima subsp. spiralis (Dumort.) Asch. & Graebn.
  • Ruppia maritima var. occidentalis (S.Watson) Graebn.
  • Ruppia maritima var. pedunculata Hartm. ex Ledeb.
  • Ruppia maritima var. spiralis (Dumort.) Moris
  • Ruppia occidentalis S.Watson
  • Ruppia spiralis J.K.Fisch.
  • Ruppia spiralis Dumort.
  • Ruppia truncatifolia Miki

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.