Euphorbiaceae

Euphorbiaceae is a family of flowering plants belonging to the eudicots (dicots with two cotyledons). The family is recognized by the milky latex that emerges when a stem or leaf is cut, though not all species possess this feature. The family contains thousands of species distributed across tropical and temperate regions worldwide.

Species within the family are highly diverse in appearance: some are large trees, others small shrubs, some tree-like succulents, and still others fleshy plants that resemble cacti but are unrelated to them. This diversity arises from their ability to inhabit both arid and wet environments.

Plant characteristics

Euphorbiaceae flowers are typically small and unisexual—with male and female flowers separate. In the genus Euphorbia, flowers are arranged in a structure called a cyathium: a cluster of male flowers surrounding a single female flower, which appears as a single flower. Fruits are usually three-celled capsules that split open when ripe, dispersing seeds.

Latex and toxins

The milky latex contains chemical compounds that deter animal consumption. In many species, the latex irritates the mouth and eyes, and it is advised not to touch it bare-handed. Some species have highly toxic seeds, notably the castor bean (Ricinus communis), whose seeds contain the poison ricin.

Economic importance

The family includes several plants of major economic importance. Cassava (Manihot esculenta) is a staple food for large populations in Africa, Asia, and South America. The rubber tree (Hevea brasiliensis) is the principal source of natural rubber. The castor bean yields industrial oil. Poinsettia (Euphorbia pulcherrima) is grown ornamentally.

Classification and revision

The classification of Euphorbiaceae has changed since DNA sequencing began. Groups formerly placed in the family are now recognized as separate families, such as Phyllanthaceae and Putranjivaceae. As a result, the meaning of "Euphorbiaceae" in older literature is broader than in current use.