Other Definitions
euphorbiaceae (dict)
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EuphorbiaceaeSee text
Ref: Euphorbiaceae in
'The Families of Flowering Plants',
as of 2002-07-13 The Spurge family (Euphorbiaceae) is a large family of flowering plants with 280 genera and around 6'000 species. Most are herbs, but some, especially in the Tropics, are also shrubs or trees. Some are succulent and resemble cacti. This family occurs mainly in the Tropics, with the majority of the species in the Indo-Malayan region and tropical South America a good second. However, Euphorbia also has many species in non-tropical areas such as the Mediterranean, the Middle East, South Africa and southern USA. The leaves are alternate, seldom opposed, with stipules. They are mainly simple. But when they are compound, they are always palmate, never pinnate. The stipules may be reduced to hairs, glands or spines. The radially symmetrical flowers are unisexual, with the male and the female flowers usually occurring on the same plant. As can be expected from such a large family, there is a wide variety in the structure of the flowers. They can be monoecious or dioecious. The stamens (the male organs) can number from 1 to 10 (or even more). The female flowers are hypogynous, i.e. with a superior ovary. The genera Euphorbia and Chamaesyce show a highly specialized form of inflorescence, called a cyathium. This is usually a small cup-like involucre. This consists of peripheral horseshoe-shaped nectaries surrounding a ring of male flowers, consisting of a single stamen. In the middle of it, stands the female flower with a single pistil with branched stigmas. This whole arrangement resembles a single flower. The fruit is usually a schizocarp, sometimes a drupe. A typical schizocarp is the regma, a capsular fruit with three or more cells, each of which splits open at maturity into separate parts and then break away with explosion. Milky juice is a characteristic of the tribe Euphorbiae of this family, in species such as Euphorbia virosa, but is mostly lacking in the other tribes. This milky sap is poisonous. Uses A number of plants of the Spurge family are of considerable economic importance. Prominent plants include manioc, rubber (from Hevea brasiliensis), and the Castor bean. Some are grown as ornamentals, such as the poinsettia (Euphorbia pulcherrima). Taxonomy The family Euphorbiaceae is divided in subfamilies, tribes and subtribes. Also note that, until recently, the Euphorbiaceae also included the subfamily of Phyllanthoideae. This latter has just been taken apart as a result of genetic lineage analyses and promulgated to the rank of family (Phyllanthaceae). - Subfamily Acalyphoideae
- Acalypheae
- Adelieae
- Agrostistachydeae
- Alchorneae
- Ampereae
- Bernardieae
- Caryodendreae
- Chaetocarpeae
- Cheiloseae
- Chrozophoreae
- Clutieae
- Dicoelieae
- Epiprineae
- Erismantheae
- Galearieae
- Omphaleae
- Pereae
- Plukenetieae
- Pogonophoreae
- Pycnocomeae
- Sphyranthereae
- Subfamily Crotonoideae
- Adenoclineae
- Aleuritideae
- Codiaeae
- Crotoneae
- Elateriospermeae
- Gelonieae
- Jatropheae
- Manihoteae
- Micrandreae
- Ricinocarpeae
- Ricinodendreae
- Trigonostemoneae
- Subfamily Euphorbioideae
- Euphorbieae
- Hippomaneae
- Hureae
- Pachystromateae
- Stomatocalyceae
- Subfamily Oldfieldioideae
- Caletieae
- Croizatieae
- Picrodendreae
- Podocalyceae
Genera References
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