Euphorbia

The plants are annual or perennial herbs, woody shrubs or trees with a caustic, poisonous milky sap (latex). The roots are fine or thick and fleshy or tuberous. Many species are more or less succulent, thorny or unarmed. The main stem and mostly also the side arms of the succulent species are thick and fleshy, 15-91 cm (6-36 inches) tall. The deciduous leaves are opposite, alternate or in whorls. In succulent species the leaves are mostly small and short-lived. The stipules are mostly small, partly transformed into spines or glands, or missing.

Like all members of the family Euphorbiaceae, all spurges have unisexual flowers. In Euphorbia these are greatly reduced and grouped into pseudanthia called cyathia. The majority of species are monoecious (bearing male and female flowers on the same plant), although some are dioecious with male and female flowers occurring on different plants. It is not unusual for the central cyathia of a cyme to be purely male, and for lateral cyathia to carry both sexes. Sometimes young plants or those growing under unfavourable conditions are male only, and only produce female flowers in the cyathia with maturity or as growing conditions improve. The bracts are often leaf-like, sometimes brightly coloured and attractive, sometimes reduced to tiny scales. The fruits are three (rarely two) compartment capsules, sometimes fleshy but almost always ripening to a woody container that then splits open (explosively). The seeds are 4-angled, oval or spherical, and in some species have a caruncle.

Selected species

See List of Euphorbia species for complete list.

• Euphorbia albomarginata – Rattlesnake Weed, White-margined Sandmat
• Euphorbia amygdaloides – Wood Spurge
• Euphorbia antisyphilitica – Candelilla
• Euphorbia bulbispina
• Euphorbia cyparissias – Cypress Spurge
• Euphorbia decidua
• Euphorbia elastica – (Mexican) Palo Amarillo
• Euphorbia epithymoides – Cushion Spurge
• Euphorbia esula – Leafy Spurge
• Euphorbia franckiana
• Euphorbia helioscopia – Sun Spurge
• Euphorbia heterophylla – Painted Euphorbia, Desert Poinsettia, (Mexican) Fireplant, Paint Leaf, Kaliko
• Euphorbia labatii
• Euphorbia lactea – Mottled Spurge, Frilled Fan, Elkhorn
• Euphorbia lathyris – Caper Spurge, Paper Spurge, Gopher Spurge, Gopher Plant, Mole Plant
• Euphorbia maculata – Spotted Spurge, Prostrate Spurge
• Euphorbia maritae
• Euphorbia milii – Crown-of-thorns, Christ Plant
• Euphorbia myrsinites – Myrtle Spurge, Creeping Spurge, donkey tail
• Euphorbia paralias – Sea Spurge
• Euphorbia peplis – Purple Spurge
• Euphorbia peplus – Petty Spurge
• Euphorbia pulcherrima – Poinsettia, Mexican Flame Leaf, Christmas Star, Winter Rose, Noche Buena, Lalupatae, Pascua, Atatürk çiçeği (Turkish)
• Euphorbia resinifera – Resin Spurge
• Euphorbia serrata – Serrated spurge, Sawtooth spurge
• Euphorbia tirucalli – Indian Tree Spurge, Milk Bush, Pencil Tree
• Euphorbia tithymaloides – Devil's Backbone, "Redbird cactus", cimora misha (Peru)
• Euphorbia virosa