Richardia scabraL.

rough Mexican clover

WFO wfo-0000127053 Accepted WFO 2026-06 8 photographs CC0 / CC BY / CC BY-SA

Plate 1 figs. a–h · 8 separate observations

Richardia scabra, photographed by Leila Dasher
fig. a Leila Dasher, CC BY 4.0 / 2022-06-05 / obs. 203845719
Richardia scabra, photographed by Ong Jyh Seng
fig. b Ong Jyh Seng, CC BY-SA 4.0 / obs. 198501756
Richardia scabra, photographed by 葉子
fig. c 葉子, CC0 1.0 / obs. 204394695
Richardia scabra, photographed by Andrés Ramírez-Barrera
fig. d Andrés Ramírez-Barrera, CC BY 4.0 / obs. 174021894
Richardia scabra, photographed by Andrés Ramírez-Barrera
fig. e Andrés Ramírez-Barrera, CC BY 4.0 / obs. 174021880
Richardia scabra, photographed by Jake Rehage
fig. f Jake Rehage, CC BY 4.0 / obs. 160688073
Richardia scabra, photographed by Jake Rehage
fig. g Jake Rehage, CC BY 4.0 / obs. 158835593
Richardia scabra, photographed by S.MORE
fig. h S.MORE, CC0 1.0 / obs. 156246021

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 39 botanical countries

Regions where Richardia scabra is native: Alabama, Arkansas, Florida, Georgia, Louisiana, Mexico Central, Mexico Gulf, Mexico Northeast, Mexico Northwest, Mexico Southeast, Mexico Southwest, Mississippi, North Carolina, South Carolina, Texas, Virginia, Argentina Northwest, Belize, Bolivia, Brazil North, Brazil Northeast, Brazil Southeast, Brazil West-Central, Central American Pacific Is., Colombia, Costa Rica, Cuba, Ecuador, El Salvador, French Guiana, Guatemala, Guyana, Honduras, Jamaica, Nicaragua, Panamá, Paraguay, Peru, Venezuela AlabamaArkansasFloridaGeorgiaLouisianaMexico CentralMexico GulfMexico NortheastMexico NorthwestMexico SoutheastMexico SouthwestMississippiNorth CarolinaSouth CarolinaTexasVirginiaArgentina NorthwestBelizeBoliviaBrazil NorthBrazil NortheastBrazil SoutheastBrazil West-CentralCentral American Pacific Is.ColombiaCosta RicaCubaEcuadorEl SalvadorFrench GuianaGuatemalaGuyanaHondurasJamaicaNicaraguaPanamáParaguayPeruVenezuela
Native distribution of Richardia scabra, 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.
RegionTDWG codeContinent
Argentina Northwest AGW SOUTHERN AMERICA
Belize BLZ
Bolivia BOL
Brazil North BZN
Brazil Northeast BZE
Brazil Southeast BZL
Brazil West-Central BZC
Central American Pacific Is. CPI
Colombia CLM
Costa Rica COS
Cuba CUB
Ecuador ECU
El Salvador ELS
French Guiana FRG
Guatemala GUA
Guyana GUY
Honduras HON
Jamaica JAM
Nicaragua NIC
Panamá PAN
Paraguay PAR
Peru PER
Venezuela VEN
Alabama ALA NORTHERN AMERICA
Arkansas ARK
Florida FLA
Georgia GEO
Louisiana LOU
Mexico Central MXC
Mexico Gulf MXG
Mexico Northeast MXE
Mexico Northwest MXN
Mexico Southeast MXT
Mexico Southwest MXS
Mississippi MSI
North Carolina NCA
South Carolina SCA
Texas TEX
Virginia VRG

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 89 in flower of 95 examined

Peak flowering in Jan. Each bar is the share of Richardia scabra 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. 89 of 95 examined observations were in flower, every one of them research grade. The whisker on each bar is a 95% Wilson interval. One month has fewer than 5 examined observations, so no proportion is drawn for it. 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.

Where it actually grows measured, from 734 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low 3.3 °C 11.9 °C 23.5 °C
Warmest month, mean daily high 25.9 °C 30.5 °C 33.6 °C
Annual rainfall 760 mm 1,354 mm 3,370 mm
Rainfall in the driest quarter 12 mm 156 mm 483 mm

It is found where winters are cool but frost is light or absent. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 734 research-grade observations of Richardia scabra 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. Climate from CHELSA V2.1 (Karger et al. 2017); occurrences from 10.15468/dl.cgje2x.

Also published as 11 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.

  • Plethyrsis glauca Raf.
  • Richardia cubensis A.Rich.
  • Richardia pilosa Ruiz & Pav.
  • Richardia procumbens Sessé & Moc.
  • Richardia scabra var. chacoensis E.L.Cabral & Bacigalupo
  • Richardia shaoyoukengensis S.S.Ying
  • Richardsonia cubensis A.Rich.
  • Richardsonia pilosa (Ruiz & Pav.) Kunth
  • Richardsonia scabra (L.) A.St.-Hil.
  • Spermacoce hirsuta Willd.
  • Spermacoce involucrata Pursh

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. USDA PLANTS Database. common name, checklist symbol RISC. public domain. 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.