Achyranthes bidentataBlume

Ox KneeJapanese chaff flower

WFO wfo-0000516220 Accepted WFO 2026-06 8 photographs CC0 / CC BY

Plate 1 figs. a–h · 8 separate observations

Achyranthes bidentata, photographed by Emily Summerbell
fig. a Emily Summerbell, CC BY 4.0 / 2021-11-27 / obs. 170600832
Achyranthes bidentata, photographed by Melissa McMasters
fig. b Melissa McMasters, CC BY 4.0 / obs. 167810407
Achyranthes bidentata, photographed by Erin Lalime
fig. c Erin Lalime, CC BY 4.0 / obs. 160785519
Achyranthes bidentata, photographed by Yann Kemper
fig. d Yann Kemper, CC0 1.0 / obs. 140094494
Achyranthes bidentata, photographed by Emily Summerbell
fig. e Emily Summerbell, CC BY 4.0 / obs. 84800228
Achyranthes bidentata, photographed by Emily Summerbell
fig. f Emily Summerbell, CC BY 4.0 / obs. 76257540
Achyranthes bidentata, photographed by Emily Summerbell
fig. g Emily Summerbell, CC BY 4.0 / obs. 74641709
Achyranthes bidentata, photographed by Emily Summerbell
fig. h Emily Summerbell, CC BY 4.0 / obs. 78883329

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 36 botanical countries

Regions where Achyranthes bidentata is native: China North-Central, China South-Central, China Southeast, Hainan, Japan, Korea, Nansei-shoto, Ogasawara-shoto, Taiwan, Tibet, Assam, Bangladesh, Borneo, Cambodia, East Himalaya, India, Jawa, Laos, Lesser Sunda Is., Malaya, Maluku, Myanmar, Nepal, New Guinea, Nicobar Is., Pakistan, Philippines, Solomon Is., Sri Lanka, Sulawesi, Sumatera, Thailand, Vietnam, West Himalaya, Caroline Is., Marianas China North-CentralChina South-CentralChina SoutheastHainanJapanTaiwanTibetAssamBangladeshBorneoCambodiaEast HimalayaIndiaJawaLaosLesser Sunda Is.MalayaMalukuMyanmarNepalNew GuineaPakistanPhilippinesSolomon Is.Sri LankaSulawesiSumateraThailandVietnamWest Himalaya KoreaNansei-shotoNicobar Is.Caroline Is.Marianas
Native distribution of Achyranthes bidentata, 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
Assam ASS ASIA-TROPICAL
Bangladesh BAN
Borneo BOR
Cambodia CBD
East Himalaya EHM
India IND
Jawa JAW
Laos LAO
Lesser Sunda Is. LSI
Malaya MLY
Maluku MOL
Myanmar MYA
Nepal NEP
New Guinea NWG
Nicobar Is. NCB
Pakistan PAK
Philippines PHI
Solomon Is. SOL
Sri Lanka SRL
Sulawesi SUL
Sumatera SUM
Thailand THA
Vietnam VIE
West Himalaya WHM
China North-Central CHN ASIA-TEMPERATE
China South-Central CHC
China Southeast CHS
Hainan CHH
Japan JAP
Korea KOR
Nansei-shoto NNS
Ogasawara-shoto OGA
Taiwan TAI
Tibet CHT
Caroline Is. CRL PACIFIC
Marianas MRN

Not drawn on the map: Ogasawara-shoto. 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.

Flowering 96 in flower of 258 examined

Peak flowering in Aug. Each bar is the share of Achyranthes bidentata 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. 96 of 258 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. 3 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 30 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.

  • Achyranthes aspera var. fruticosa (Lam.) Boerl.
  • Achyranthes bidentata f. rubra F.C.Ho
  • Achyranthes bidentata var. bidentata Blume
  • Achyranthes bidentata var. hachijoensis (Honda) H.Hara
  • Achyranthes bidentata var. japonica Miq.
  • Achyranthes bidentata var. longifolia Makino
  • Achyranthes bidentata var. tomentosa (Honda) H.Hara
  • Achyranthes bidentata var. villosa J.L.Liu
  • Achyranthes chinensis Osbeck
  • Achyranthes fauriei H.Lév. & Vaniot
  • Achyranthes fauriei f. rotundifolia Ohwi
  • Achyranthes fauriei var. tomentosa Honda
  • Achyranthes fruticosa Lam.
  • Achyranthes hispida Moq.
  • Achyranthes japonica (Miq.) Nakai
  • Achyranthes japonica var. hachijoensis Honda
  • Achyranthes japonica var. katsuudakemontana Tawada
  • Achyranthes javanica Moq.
  • Achyranthes lanceolata Klein bis ex Wall.
  • Achyranthes longifolia (Makino) Makino
  • Achyranthes longifolia f. rubra F.C.Ho
  • Achyranthes megaphylla Y.H.Li
  • Achyranthes mollicula Nakai
  • Achyranthes ogatai Yamam.

and 6 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.