Euphorbia caput-medusae L.

First published in Sp. Pl.: 452 (1753)
This species is accepted
The native range of this species is SW. Namibia to W. & SW. Cape Prov. It is a succulent subshrub and grows primarily in the desert or dry shrubland biome.

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation
Predicted extinction risk: not threatened. Confidence: confident
[AERP]

Kew Species Profiles

General Description
Medusa's head is so named because of its numerous snake-like stems.

There are more than 2,000 species of Euphorbia (spurge). They range widely in habit from trees and succulent perennials to small annual herbs. They all produce caustic milky sap.

Euphorbia caput-medusae was introduced from South Africa to the Netherlands around 1700 and described by Linnaeus in his Species Plantarum (1753). Linnaeus had previously worked for George Clifford, a banker and one of the directors of the Dutch East India Company (Verenigde Oostindische Compagnie, VOC). Clifford owned a garden (Hartekamp) near Haarlem, in which he grew a great variety of plants, many sent to him by VOC employees in the Cape. As a result, Linnaeus had an unrivalled opportunity to get to know some of the South African plants coming into Europe at that time, and his work in cataloguing Clifford's plants, published in 1737 as Hortus Cliffortianus, was to stand him in good stead when he came to organise his later work.

The Latin (and common) name 'head of Medusa' describes the plant well, and it is likely that this was among the species grown in Clifford's garden.

Species Profile
Geography and distribution

Endemic to the Cape region of South Africa, from Namaqualand to Mossel Bay.

Description

Euphorbia caput-medusae is a sprawling, succulent shrub, reaching 1 m across. It has a rosette of narrow, snake-like, spineless but knobbly branches, each 10-30 mm in diameter that arise from a short woody stem (caudex) and which rapidly lose their leaves . The remaining narrow, fleshy leaves and a cluster of inflorescences are carried at the end of the branches.

The specialised inflorescences (cyathia) each have a cup-shaped involucre (a whorl of bracts around or beneath the inflorescence) that is 12 mm or more across, with five incurved (bent inwards) lobes and five green shining glands. Each gland is divided into 3-6 white linear or forked processes (outgrowths) which form a fringe around the individual male flowers, each of which has a single stamen, and the single female flower with an elongated pedicel (flower stalk).

Illustration from Curtis's Botanical Magazine

The specimen figured in the featured illustration by Matilda Smith was drawn from the garden of La Mortola, Italy, 'where it flowered in March 1916 - the only difference from the wild plant being in its considerably thicker branches.'

Kew paintings of Medusa's head

Matilda Smith, who painted the image in  Curtis's Botanical Magazine , was a relation of Joseph Dalton Hooker, Director of Kew from 1865-1885. Hooker trained her as a botanical artist by getting her to draw from living specimens as well as to copy drawings from  Curtis's Botanical Magazine . In 1898 she became the first official paid artist at Kew.

Uses

Euphorbia caput-medusae is cultivated as an ornamental, and is a particular favourite of succulent plant enthusiasts.

This species at Kew

Medusa's head is grown behind the scenes, in the Tropical Nursery at Kew.

Kew's Economic Botany Collection includes a sample of the acrid milky juice from Euphorbia caput-medusae that was donated to Kew by the artist Thomas Baines in 1854. It is available to researchers from around the world, by appointment.

Distribution
South Africa
Ecology
Sandy flats and rocky coastal outcrops.
Conservation
Least Concern (LC) according to the Red List of South African Plants 2009, following IUCN Red List criteria.
Hazards

The milky sap (latex) is a skin and eye irritant.

[KSP]

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation
Predicted extinction risk: not threatened. Confidence: low confidence
[AERP]

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation
Predicted extinction risk: threatened. Confidence: confident
[AERP]

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation
Predicted extinction risk: threatened. Confidence: confident
[AERP]

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation
Predicted extinction risk: threatened. Confidence: confident
[AERP]

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation
Predicted extinction risk: not threatened. Confidence: confident
[AERP]

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation
Predicted extinction risk: threatened. Confidence: confident
[AERP]

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation
Predicted extinction risk: threatened. Confidence: confident
[AERP]

Uses

Use
Ornamental.
[KSP]

Common Names

English
Medusa's head

Sources

  • Angiosperm Extinction Risk Predictions v1

    • Angiosperm Threat Predictions
    • http://creativecommons.org/licenses/by/4.0
  • Herbarium Catalogue Specimens

    • Digital Image © Board of Trustees, RBG Kew http://creativecommons.org/licenses/by/3.0/
  • Kew Backbone Distributions

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0
  • Kew Names and Taxonomic Backbone

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 International Plant Names Index and World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0
  • Kew Science Photographs

    • Copyright applied to individual images
  • Kew Species Profiles

    • Kew Species Profiles
    • http://creativecommons.org/licenses/by-nc-sa/3.0