This member of the Euphorbiaceae family was given this name by Pierre Edmond Boissier in 1862. It is found in Eswatini, Botswana, Lesotho and South Africa, growing in a well drained soil with some water and some sun. The caudex can grow to three centimetres, the plant up to fifteen or even 30 centimetres. The flowers are mauve with white and magenta markings.
The genera name; Euphorbia dates back to the first century BC, where King Juba II of Mauritania used it in a reference to his doctor, Euphorbos, and that name was kept as a generic name by Carl von Linnaeus. The species name for Wilhelm Gueinzius, 1814-1874, a German apothecary and naturalist, emigrated to South Africa.
This plant CAN grow as a wither-grower. Euphorbia guenzii var albivillosa by Graham G, Ispotnature.org.

