Thuarea involuta(G.Forst.) R.Br. ex Sm.

Kuroiwa grass

WFO wfo-0000903686 Accepted WFO 2026-06 8 photographs CC0 / CC BY / CC BY-SA

Plate 1 figs. a–h · 8 separate observations

Thuarea involuta, photographed by Steve Fitzgerald
fig. a Steve Fitzgerald, CC BY-SA 4.0 / 2022-05-02 / obs. 193418589
Thuarea involuta, photographed by Greg Tasney
fig. b Greg Tasney, CC BY-SA 4.0 / obs. 186622634
Thuarea involuta, photographed by Emanuele Santarelli
fig. c Emanuele Santarelli, CC BY-SA 4.0 / obs. 187928079
Thuarea involuta, photographed by 葉子
fig. d 葉子, CC0 1.0 / obs. 129821271
Thuarea involuta, photographed by 葉子
fig. e 葉子, CC0 1.0 / obs. 129815304
Thuarea involuta, photographed by 葉子
fig. f 葉子, CC0 1.0 / obs. 63465922
Thuarea involuta, photographed by 葉子
fig. g 葉子, CC0 1.0 / obs. 62296083
Thuarea involuta, photographed by 國立臺灣博物館
fig. h 國立臺灣博物館, CC BY 4.0 / obs. 57708671

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 48 botanical countries

Regions where Thuarea involuta is native: Madagascar, China Southeast, Hainan, Kazan-retto, Nansei-shoto, Ogasawara-shoto, Taiwan, Andaman Is., Bangladesh, Bismarck Archipelago, Borneo, Cambodia, Cocos (Keeling) Is., Jawa, Laccadive Is., Lesser Sunda Is., Malaya, Maldives, Maluku, New Guinea, Nicobar Is., Philippines, Solomon Is., South China Sea, Sulawesi, Sumatera, Thailand, Vietnam, Northern Territory, Queensland, Caroline Is., Cook Is., Fiji, Gilbert Is., Hawaii, Marianas, Marshall Is., New Caledonia, Pitcairn Is., Samoa, Santa Cruz Is., Society Is., Tonga, Tuamotu, Tubuai Is., Tuvalu, Vanuatu, Wallis-Futuna Is. MadagascarChina SoutheastHainanTaiwanBangladeshBismarck ArchipelagoBorneoCambodiaJawaLesser Sunda Is.MalayaMalukuNew GuineaPhilippinesSolomon Is.SulawesiSumateraThailandVietnamNorthern TerritoryQueenslandFijiHawaiiNew Caledonia Nansei-shotoAndaman Is.Laccadive Is.MaldivesNicobar Is.South China SeaCaroline Is.Cook Is.MarianasMarshall Is.Pitcairn Is.SamoaSociety Is.TongaTuamotuTubuai Is.TuvaluVanuatuWallis-Futuna Is.
Native distribution of Thuarea involuta, 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
Andaman Is. AND ASIA-TROPICAL
Bangladesh BAN
Bismarck Archipelago BIS
Borneo BOR
Cambodia CBD
Cocos (Keeling) Is. CKI
Jawa JAW
Laccadive Is. LDV
Lesser Sunda Is. LSI
Malaya MLY
Maldives MDV
Maluku MOL
New Guinea NWG
Nicobar Is. NCB
Philippines PHI
Solomon Is. SOL
South China Sea SCS
Sulawesi SUL
Sumatera SUM
Thailand THA
Vietnam VIE
Caroline Is. CRL PACIFIC
Cook Is. COO
Fiji FIJ
Gilbert Is. GIL
Hawaii HAW
Marianas MRN
Marshall Is. MRS
New Caledonia NWC
Pitcairn Is. PIT
Samoa SAM
Santa Cruz Is. SCZ
Society Is. SCI
Tonga TON
Tuamotu TUA
Tubuai Is. TUB
Tuvalu TUV
Vanuatu VAN
Wallis-Futuna Is. WAL
China Southeast CHS ASIA-TEMPERATE
Hainan CHH
Kazan-retto KZN
Nansei-shoto NNS
Ogasawara-shoto OGA
Taiwan TAI
Northern Territory NTA AUSTRALASIA
Queensland QLD
Madagascar MDG AFRICA

Not drawn on the map: Kazan-retto, Ogasawara-shoto, Cocos (Keeling) Is., Gilbert Is., Santa Cruz 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.

Also published as 7 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.

  • Ischaemum involutum G.Forst.
  • Ornithocephalochloa arenicola Kurz
  • Panicum sarmentosum (Pers.) Raspail
  • Thuarea involucrata Eschsch.
  • Thuarea latifolia R.Br.
  • Thuarea media R.Br.
  • Thuarea sarmentosa Pers.

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.