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Family Euphorbiaceae Juss.
Сем. LXVII. МЛЕЧКОВИ - EUPHORBIACEAE JUSS.¹
Fam: Euphorbiaceae Juss.
English Name: Spurge family, Euphorbias

Description:

Trees, shrubs or perennial to annual herbaceous plants, often with milky sap. Leaves simple, successive or opposite, often reduced to thorns, with or without stipules. Flowers unisexual, dioecious or monoecious, single or grouped in racemose or umbellate inflorescences, sometimes with a common sheath resembling a single flower. Male flowers with many to one stamens and perianth of calyx and corolla or corolla reduced, or perianth reduced to small scales; stamens free or fused, simple or branched; with or without rudimentary pistil. Female flowers of one pistil, with or without perianth, with an upper 2 - 3-nested ovary, each nest with 1 - 2 hanging seed buds, with an abdominal seam at the site of attachment, often with a developed appendage. The styless 2 - 3, fused or free, two- to many-parted. The fruit is dry - a decaying box, rarely strawberry or stone. Seeds with developed endosperm, with or without appendage. Insect-pollinated, propagated mainly by seeds.

Omalanthus paraeuxinus Palam has been found in the fossil state. (Rudnik, Burgas - Upper Eocene).

Table for determination of the genera

1   The leaves are thyroid, with a hairy cut ........................................................................................................ - Ricinus L.
1* Leaves non-thyroid, the petiole at the base of the leaf .................................................................................................... 2
2 Male and female flowers with a common shell, resembling a separate flower. Plants with milk juice ....... 4. - Euphorbia L.
2* Male and female flowers separated, with a separate perianth. Plants without milk juice ................................................... 3
3    Leaves opposite .............................................................................................................................. 3. - Mercurialis L.
3* Leaves successive ................................................................................................................................................... .... 4
4   Plants with dense star-shaped hairs ........................................................................................... 2. - Chrozophora Neck.
4* Plants without star-shaped hairs .......................................................................................................... 1. - Andrachne L.
¹Developed by B. Kuzmanov

From:   „Флора на Н. Р. България”, том VII, Издателство на БАН, София, (1979)

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The Euphorbiaceae, the spurge family, are a large family of flowering plants. In common English, they are sometimes called euphorbias,[2] which is also the name of a genus in the family. Most spurges such as Euphorbia paralias are herbs, but some, especially in the tropics, are shrubs or trees, such as Hevea brasiliensis. Some, such as Euphorbia canariensis,[3]:206 are succulent and resemble cacti because of convergent evolution.[4] This family occurs mainly in the tropics, with the majority of the species in the Indo-Malayan region and tropical America a strong second. A large variety occurs in tropical Africa, but they are not as abundant or varied as in the two other tropical regions. However, the Euphorbiaceae also have many species in nontropical areas such as the Mediterranean Basin, the Middle East, South Africa, and the Southern United States.

Description

The leaves are alternate, seldom opposite, with stipules. They are mainly simple, but where compound, are always palmate, never pinnate. Stipules may be reduced to hairs, glands, or spines, or in succulent species are sometimes absent.
The plants can be monoecious or dioecious. The radially symmetrical flowers are unisexual, with the male and female flowers usually on the same plant. As can be expected from such a large family, a wide variety exists in the structure of the flowers. The stamens (the male organs) number from one to 10 (or even more). The female flowers are hypogynous, that is, with superior ovaries.
The genera in tribe Euphorbieae, subtribe Euphorbiinae (Euphorbia and close relatives) show a highly specialized form of pseudanthium ("false flower" made up of several true flowers) called a cyathium. This is usually a small, cup-like involucre consisting of fused-together bracts and peripheral nectary glands, surrounding a ring of male flowers, each a single stamen. In the middle of the cyathium stands a female flower, a single pistil with branched stigmas. This whole arrangement resembles a single flower.
The fruit is usually a schizocarp, but sometimes a drupe. A typical schizocarp is the regma, a capsular fruit with three or more cells, each of which splits open explosively at maturity, scattering the small seeds.
The family contains a large variety of phytotoxins (toxic substances produced by plants), including diterpene esters, alkaloids, and cyanogenic glycosides (e.g. root tubers of cassava). The seeds of the castor oil plant Ricinus communis contain the highly toxic carbohydrate-binding protein ricin.[5]
A milky latex is a characteristic of the subfamilies Euphorbioideae and Crotonoideae, and the latex of the rubber tree Hevea brasiliensis is the primary source of natural rubber. The latex is poisonous in the Euphorbioideae, but innocuous in the Crotonoideae.[citation needed] White mangrove, also known as blind-your-eye mangrove latex (Excoecaria agallocha), causes blistering on contact and temporary blindness if it contacts the eyes, hence its name. Other common names are milky mangrove, buta buta (Malay), and gewa (Bangladesh). The latex of spurge was used as a laxative.
Recent molecular studies have shown that the enigmatic family Rafflesiaceae, which was only recently recognized to belong to order Malpighiales, is derived from within the Euphorbiaceae.[6]

Taxonomy

Main article: List of Euphorbiaceae genera
The family Euphorbiaceae is the fifth-largest flowering plant family[7] and has about 7,500 species[8] organised into 300 genera,[7] 37 tribes, and three subfamilies.[citation needed]

From Wikipedia, the free encyclopedia

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Distribution in Bulgaria: (Conspectus of the Bulgarian Vascular Flora) = conspectus&gs_l= Zlc.
Distribution:

References: „Флора на Н. Р. България”, том VII, Издателство на БАН, София, (1979), Wikipedia, the free encyclopedia

GENERA:

Genus Euphorbia L. - Spurge

Genus Ricinus L. - Castor oil

E-mail: krnanev@gmail.com

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