Ranunculus flabellarisRaf.

yellow water buttercup

WFO wfo-0001129257 Accepted WFO 2026-06 8 photographs CC0 / CC BY

Plate 1 figs. a–h · 8 separate observations

Ranunculus flabellaris, photographed by Lynn Harper
fig. a Lynn Harper, CC0 1.0 / 2022-05-18 / obs. 198698274
Ranunculus flabellaris, photographed by Reuven Martin
fig. b Reuven Martin, CC0 1.0 / obs. 197968030
Ranunculus flabellaris, photographed by Violet T.
fig. c Violet T., CC BY 4.0 / obs. 175949366
Ranunculus flabellaris, photographed by Violet T.
fig. d Violet T., CC BY 4.0 / obs. 175940370
Ranunculus flabellaris, photographed by Violet T.
fig. e Violet T., CC BY 4.0 / obs. 175940310
Ranunculus flabellaris, photographed by Violet T.
fig. f Violet T., CC BY 4.0 / obs. 175935226
Ranunculus flabellaris, photographed by Violet T.
fig. g Violet T., CC BY 4.0 / obs. 172077924
Ranunculus flabellaris, photographed by Violet T.
fig. h Violet T., CC BY 4.0 / obs. 171690517

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 46 botanical countries

Regions where Ranunculus flabellaris is native: Alabama, Alberta, Arkansas, British Columbia, California, Connecticut, Delaware, Idaho, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Manitoba, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Nebraska, Nevada, New Brunswick, New Hampshire, New Jersey, New York, North Carolina, North Dakota, Ohio, Oklahoma, Ontario, Oregon, Pennsylvania, Québec, Rhode I., South Dakota, Tennessee, Texas, Utah, Vermont, Virginia, Washington, Wisconsin, Wyoming AlabamaAlbertaArkansasBritish ColumbiaCaliforniaConnecticutIdahoIllinoisIndianaIowaKansasKentuckyLouisianaMaineManitobaMarylandMassachusettsMichiganMinnesotaMississippiMissouriNebraskaNevadaNew BrunswickNew HampshireNew JerseyNew YorkNorth CarolinaNorth DakotaOhioOklahomaOntarioOregonPennsylvaniaQuébecSouth DakotaTennesseeTexasUtahVermontVirginiaWashingtonWisconsinWyoming DelawareRhode I.
Native distribution of Ranunculus flabellaris, 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
Alabama ALA NORTHERN AMERICA
Alberta ABT
Arkansas ARK
British Columbia BRC
California CAL
Connecticut CNT
Delaware DEL
Idaho IDA
Illinois ILL
Indiana INI
Iowa IOW
Kansas KAN
Kentucky KTY
Louisiana LOU
Maine MAI
Manitoba MAN
Maryland MRY
Massachusetts MAS
Michigan MIC
Minnesota MIN
Mississippi MSI
Missouri MSO
Nebraska NEB
Nevada NEV
New Brunswick NBR
New Hampshire NWH
New Jersey NWJ
New York NWY
North Carolina NCA
North Dakota NDA
Ohio OHI
Oklahoma OKL
Ontario ONT
Oregon ORE
Pennsylvania PEN
Québec QUE
Rhode I. RHO
South Dakota SDA
Tennessee TEN
Texas TEX
Utah UTA
Vermont VER
Virginia VRG
Washington WAS
Wisconsin WIS
Wyoming WYO

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.

Flowering 129 in flower of 155 examined

Peak flowering in May. Each bar is the share of Ranunculus flabellaris observations in which someone actually recorded the reproductive state and found the plant in flower, not the raw number of flowering records. That distinction matters: people observe plants far more in spring than in winter, so a bare count of flowering records partly measures when people go outside. Dividing by the number examined removes that. 129 of 155 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 9 months have fewer than 5 examined observations, so no proportion is drawn for them. This is still a global aggregate and not a forecast for your garden: the same species flowers on different dates in different hemispheres. Where a species has fewer than 30 flowering records we do not draw this chart at all. Computed from 10.15468/dl.cgje2x.

Also published as 6 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.

  • Ranunculus delphinifolius f. terrestris (A.Gray) S.F.Blake
  • Ranunculus delphinifolius var. terrestris (A.Gray) Farw.
  • Ranunculus flabellaris f. flabellaris
  • Ranunculus flabellaris f. plenus B.Boivin
  • Ranunculus flabellaris f. riparius Fernald
  • Ranunculus multifidus var. terrestris A.Gray

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.