Crown of thorns

Names and Synonyms

Common Names

• Christ's-plant
• Christ's-thorn
• crown-of-thorns

Scientific Names

Accepted name

Synonyms

• Sterigmanthe bojeri
• Euphorbia bojeri
• Euphorbia bojeri var. mucronulata
• Euphorbia milii var. breonii
• Euphorbia milii f. lutea
• Euphorbia milii var. milii
• Euphorbia splendens subsp. bojeri
• Euphorbia splendens var. bojeri
• Euphorbia breonii
• Tumalis bojeri

Regional and Traditional Names

Sources: Wikidata, Catalogue of Life

Taxonomical Classification

This plant belongs to the kingdom Plantae and the phylum Streptophyta, falling under the class Equisetopsida and subclass Magnoliidae. Within the order Malpighiales, it is classified under the family Euphorbiaceae. Finally, its specific taxonomic identity is defined by the genus Euphorbia.

Sources: The World Checklist of Vascular Plants (WCVP)

Distribution

This plant exhibits a diverse geographical range that spans across several distinct regions. In West Tropical Africa, its presence is noted specifically within Gambia. Moving toward the Western Indian Ocean, it can be found inhabiting both Comoros and Madagascar. The species also extends its reach into East Asia, specifically within China South-Central. Finally, its distribution includes the tropical island province of Hainan in China.

Sources: The World Checklist of Vascular Plants (WCVP)

Botanical Identification

Ecology

The ecology of Euphorbia milii is defined by its ability to thrive across a diverse altitudinal gradient, inhabiting environments ranging from an elevation of 200 m AMSL to a maximum of 1700 m AMSL. Within these varying topographical layers, the species has evolved specialized survival strategies to withstand environmental pressures, most notably through the implementation of active defense mechanisms. These biological defenses serve to protect the plant from herbivory and external stressors, ensuring its persistence within its native ecological niches.

Defense :

yes

Elevational range max:

1700 m AMSL

Elevational range min:

200 m AMSL

Life history

The life history of Euphorbia milii is characterized by its long-lived nature, functioning as a perennial organism that maintains its presence across multiple growing seasons. In terms of its structural growth habits and life forms, it exhibits characteristics of both phanerophytes, where its woody, succulent stems extend well above the ground level to form a robust structural base, and chamaephyte tendencies in certain growth stages or environmental conditions where much of the biomass remains close to the soil surface. This combination of life forms allows the plant to persist through varying environmental stressors, ensuring a continuous lifecycle through its perennial biological strategy.

Life form :

chamaephyte

Life form :

phanerophyte

Lifecycle :

perennial

Morphology

The morphology of Euphorbia milii is characterized by its growth form as a self-supporting shrub, reaching a maximum plant height of approximately 1.5 m. It is a terrestrial species, functioning as an independent organism rather than a parasite or an epiphyte. The plant exhibits a non-woody woodiness profile and is distinctly non-aquatic, maintaining a purely terrestrial existence. As a self-supporting structure, it does not function as a climber, liana, or vine, but instead maintains its upright shrubby habit through its own structural integrity.

Aquatic :

terrestrial

Climber :

self-supporting

Epiphyte :

terrestrial

Growth form :

herb

Growth form :

shrub

Parasite :

independent

Plant height max:

1.5 m

Woodiness :

non-woody

Physiology

The physiology of Euphorbia milii is characterized by distinct morphological adaptations, most notably its succulent nature, which allows for efficient water storage and survival in arid conditions. The plant's foliage exhibits significant variability in dimensions, with leaf lengths ranging from a minimum of 1.5 cm to a maximum of 5 cm, maintaining a mean length of approximately 3.25 cm. These leaves typically present an elliptic form, serving as the primary sites for photosynthesis and transpiration. In terms of transverse dimensions, the leaf width fluctuates between a minimum of 0.8 cm and a maximum of 2 cm, with an overall mean width of 1.3 cm. This combination of succulence and specific leaf geometry facilitates a physiological balance between moisture retention and gas exchange.

Leaf form :

elliptic

Leaf length max:

5 cm

Leaf length mean:

3.25 cm

Leaf length min:

1.5 cm

Leaf width max:

2 cm

Leaf width mean:

1.3 cm

Leaf width min:

0.8 cm

Succulence :

yes

Reproduction

The reproduction of Euphorbia milii is characterized by a flowering period that is highly variable, typically beginning around October and continuing through to February, though it can occur across various months of the year. The plant produces distinct red flowers that serve as a primary visual feature during its reproductive phase. Following pollination, the plant develops small fruits that maintain consistent dimensions; the fruit length is uniform at approximately 0.35 cm (with a minimum, mean, and maximum all measured at 0.35 cm), while the fruit width is also consistent at 0.4 cm (with a minimum, mean, and maximum all measured at 0.4 cm). Regarding the movement of its seeds, the species exhibits an anthropochorous dispersal syndrome, meaning its distribution is significantly influenced by human activity.

Dispersal syndrome :

anthropochorous

Flower colour :

red

Flowering time :

Oct

Flowering time :

Feb

Fruit length max:

0.35 cm

Fruit width max:

0.4 cm

Sources: Global Inventory of Floras and Traits (GIFT)

Plant Parts

Euphorbia milii has 1 reported plant parts identified across 1 scientific publications and several other databases that are studied for medicinal purposes. The most consistently reported plant part include root.

Root

1. Pakistan journal of pharmaceutical sciences

Chemicals

Euphorbia milii has 5 reported phytochemicals identified across 1 scientific publications and several other databases. The most consistently reported chemicals include ANTHOCYANIN, Cardiac Glycosides, Flavonoids, Tannins, Terpenoids.

ANTHOCYANIN

1. Pakistan journal of pharmaceutical sciences

Cardiac Glycosides

1. Pakistan journal of pharmaceutical sciences

Flavonoids

1. Pakistan journal of pharmaceutical sciences

Tannins

1. Pakistan journal of pharmaceutical sciences

Terpenoids

1. Pakistan journal of pharmaceutical sciences

Activities

Euphorbia milii has 4 reported activities identified across 1 scientific publications and several other databases. The most consistently reported activities include Antibacterial, Antimicrobial, Antioxidant, Molluscicide.

Antibacterial

1. Pakistan journal of pharmaceutical sciences
2. International journal of health sciences

Antimicrobial

1. Pakistan journal of pharmaceutical sciences

Antioxidant

1. Pakistan journal of pharmaceutical sciences

Molluscicide

1. Biophysical chemistry

Medicinal Uses

Euphorbia milii has 4 reported medicinal uses identified across 1 scientific publications and several other databases. The most consistently reported uses include Schistosomiasis, boils, infectious diseases, pain.

Most Reported Uses

Preparations