Euphorbia rigidaM.Bieb.

upright myrtle spurge

WFO wfo-0000964438 Accepted WFO 2026-06 8 photographs CC BY

Plate 1 figs. a–h · 8 separate observations

Euphorbia rigida, photographed by hecklemore
fig. a hecklemore, CC BY 4.0 / 2022-04-19 / obs. 191048635
Euphorbia rigida, photographed by Ben Costamagna
fig. b Ben Costamagna, CC BY 4.0 / obs. 188827324
Euphorbia rigida, photographed by Bob Walker
fig. c Bob Walker, CC BY 4.0 / obs. 197038821
Euphorbia rigida, photographed by hecklemore
fig. d hecklemore, CC BY 4.0 / obs. 186009052
Euphorbia rigida, photographed by Julien Tchilinguirian
fig. e Julien Tchilinguirian, CC BY 4.0 / obs. 174829897
Euphorbia rigida, photographed by Riccardo Guarino
fig. f Riccardo Guarino, CC BY 4.0 / obs. 172562693
Euphorbia rigida, photographed by Kristof Zyskowski
fig. g Kristof Zyskowski, CC BY 4.0 / obs. 123315479
Euphorbia rigida, photographed by Михаил Орлов
fig. h Михаил Орлов, CC BY 4.0 / obs. 109387683

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
04336212
Filed as
Euphorbia rigida M.Bieb.
Det. by
not recorded on this sheet
Collected
Collector unknown 1896-05-28
Origin
UA
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 16 botanical countries

Regions where Euphorbia rigida is native: Algeria, Morocco, East Aegean Is., Iran, Lebanon-Syria, North Caucasus, Türkiye, Albania, Greece, Kriti, Krym, NW. Balkan Pen., Romania, Sicilia, Türkiye-in-Europe, Ukraine AlgeriaMoroccoEast Aegean Is.IranLebanon-SyriaNorth CaucasusTürkiyeAlbaniaGreeceKritiKrymNW. Balkan Pen.RomaniaSiciliaTürkiye-in-EuropeUkraine
Native distribution of Euphorbia rigida, 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
Albania ALB EUROPE
Greece GRC
Kriti KRI
Krym KRY
NW. Balkan Pen. YUG
Romania ROM
Sicilia SIC
Türkiye-in-Europe TUE
Ukraine UKR
East Aegean Is. EAI ASIA-TEMPERATE
Iran IRN
Lebanon-Syria LBS
North Caucasus NCS
Türkiye TUR
Algeria ALG AFRICA
Morocco MOR

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 596 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -2.7 °C 0.6 °C 8.4 °C
Warmest month, mean daily high 21.7 °C 26.2 °C 33.1 °C
Annual rainfall 457 mm 798 mm 1,165 mm
Rainfall in the driest quarter 4 mm 68 mm 177 mm

It is found where winters bring light frost. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 596 research-grade observations of Euphorbia rigida 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 9 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.

  • Euphorbia biglandulosa Desf.
  • Euphorbia biglandulosa var. mauretanica Maire
  • Euphorbia phlomos P.Candargy
  • Euphorbia pungens [Soland.]
  • Euphorbia rigida var. mauretanica (Maire) Oudejans
  • Euphorbia suffruticosa Forssk.
  • Galarhoeus rigidus (M.Bieb.) Haw.
  • Tithymalus biglandulosus (Desf.) Haw.
  • Tithymalus rigidus (M.Bieb.) Soják

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.