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Genus Euphoria L.

Род 472 (4). МЛЕЧКА - EUPHORBIA L.
L., Sp. Pl. ed. 1 (1753) 450; Gen. Pl. ed. 5 (1754) 208; Boiss. in DC., Prodr. XV, 2 (1862) 7

Fam:   Euphorbiaceae Juss.
Genus:   Euphoria L.
English Name: Spurge

Description:

Arboreal plants, shrubs or perennial to annual herbaceous plants with milky sap formed in numerous not branched cells. Stems sometimes fleshy, leaves more or less reduced, often turned into thorns or woody or herbaceous and leaves developed, herbaceous; always simple entire, toothed or fine serrated, successive or opposite, with or without stipules. The flowers are unisexual. Males from one stamen and small appendage, females from one pistil, usually without bracts. Monoecious plants. The male flowers of (5) 10 - 40 (50), collected with one female flower in a simple inflorescence - ciatium, with a sheath - perianth (pericyatium), formed by the adhesion of the bracts of male flowers, ¹ often by 4 – 5 (rarely 1 or more than 5) fleshy appendages - glands; cyatiums single in the axils of the stem leaves or more often forming apical dichases or in complex umbellate inflorescences - pleiochasia; the apical dichasias at the base with 2 - 3 bract leaflets ², the pleiochasias at the base with several bracts; rarely individual branches of dichases develop into monochases. The pistil of 3 carpels, with an upper trifoliate ovary, each nest with 1 seed bud; columns, usually fused at the base.3 The fruit is dry, decaying box (regma). The seed is smooth or with various relief formations, usually with or without an appendix (caruncle). Insect-pollinated, propagated by seeds and less often by vegetative shoots. Insects are attracted by the nectar of the glands, the seeds are dispersed when the box cracks or by various animals (exo- or endozoochoria).

¹ See table. XXVI: FIG. 1, 1a, 16; page 123.
² Bracts used for conciseness, as cyatiums have the biological role of flowers.
3 The columns are also entrenched in the ripe fruit and have significant diagnostic value.

Economic significance. Due to the content of poisonous substances in the milk juice of all species, they can cause poisoning in domestic animals and humans. A number of species (E. glareosa, E. niciciapa, E. cyparissias), which grow en masse on pastures, compete with valuable fodder grasses, tolerate trampling too well and, due to their toxicity, are avoided by animals, as a result of which reduce pasture productivity. Some species are weeds in cereals and cereals (E. cyparissias, E. seguerana, E. agraria, E. esula, E. helioscopia, E. falcata). Many species {E. agraria, E. cyparissias, E. glareosa, E., amygdaloides, E. nicichiapa, E. helioscopia, etc.) are intermediate hosts of a number of fungi parasitizing on important crops. Some species (E. polychroma, E. villosa, E. velenovskyi, E. lucicla) can be used as ornamentals.

Table for determination of the species

1    Stem leaves basically asymmetrical, opposite …………………………….….....................................................……………. 2
1* Stem leaves basically symmetrical, consecutive, rarely in vertebrae of four …….........................................................………… 6
2    Bare plant, fleshy leaves. The seed is smooth…………………....................................................…………... 28. - E. peplis L.
2* Densely fibrous to naked plant, fleshy leaves. Seeds wrinkled, warty or streaked …….......................................................…… 3
3   Ovary and fibrous box …………………………..………………………..................................................…………………. 5
3* The ovary and the box are bare …………………………………………....................................................………………… 4
4    The leaves (1) 3 - 7 (-11) mm long and (1) 2 - 4 (6) mm wide, indistinctly serrated to almost entire .... .. 27. - E. chamaesyce L.
4* Leaves 10 - 30 (-36) mm long and 5 - 10 (- - 15) mm wide, clearly dotted ………… ....................................…. E. nutans Lag.
5    Appendages (1) 2 - 3 (5) times wider than glands. The seed is coarse-grained ……..................…......... 27. - E. chamaesyce L.
5* Appendages equal in width to the glands or narrower. The seed is furrowed ……….……………………….…. - E. maculata L.
6    Bracts with a broad white stripe or whole white ………...……......................................................…… * - E. marginata Pursh
6* Bracts without white stripe, non-white ………………….........................................................……………………………… .. 7
7    Stem leaves 4, in the vertebrae of the cross  ………….....................................................…………………….... - E. lathyris L.
7* Stem leaves consecutive ……… ………………………………….....................................................……………………… .. 8
8   The pistil and the box with long filamentous, cylindrical or warty formations. The leaves in the upper half serrated or serrated,
rarely entire; glands entire; seeds brown  …….............................................................................................................…………… 9
8* The pistil without growths, the box smooth (rarely grainy rough, but then the glands are crescent or with horns). Leaves entire or
sparsely toothed to dusted; glands usually with horns; seeds gray to gray-black (or rarely dark brown) ........................................... 16
9   Annuals or biennials …………………………………………….....................................................………...………………. 10
9* Perennials …………………… ... ………………………....................................................……………………………… .. 11
10 The box with warty growths, 2.5 - 3.0 (5) mm long and 3.0 - 3.5 (4.0) mm wide; seeds 2.0 - 2.2 mm long, dark brown ...............  …………………………………….............................................................................................…..…… 7. - E. plathyphyllos L.
10* The box with cylindrical projections, 1.8 - 2.0 mm long and 2.0 - 2.5 mm wide; seeds 1.4 - 1.5 mm long, copper brown ........... .................................................................................................................................................................... 8. - E. serrulata Thuill.
11    The root thickened in the form of a tuber ........................................................................................................... 1. - E. apios L.
11* The root is not thickened in the form of a tuber ....................................................................................................................... 12
12   Stem and leaves bare above (rarely young fibrous stems) ....................................................................................................... 13
12* Stem and leaves on top more or less fibrous .......................................................................................................................... 14
13  Stem leaves pointed, with a clear cartilaginous edge, from the middle upwards sharp serrated ...................................................... ………………………………………………................................................................……….…… 6. - E. velenovskyi Bornm.
13* Stem leaves blunt, without cartilaginous edge (or with a narrow light stripe), entire or indistinctly dusted on top .......................... .......................................................................................................................................................................... 5. - E. palustris L.
14   Box with dense, up to 1.2 mm long, filamentous, yellow, yellow-green or purple fleshy growths ......... 4. - E. polychroma Kern.
14* The box with short, warty, green or yellow-green growths ..................................................................................................... 15
15   The glands around the inflorescence 3, rarely 4, the styles at the apex shallowly bipartite ..................... 3. - E. oblongata Griseb.
15* The glands around the inflorescence 4, the styles from the top of 1/2 bipartite …….........……….. 2. - E. villosa Waldst. et Kit.
16    Seeds dark brown ............................................................................................................................................................... 17
16* Seed gray to gray black ........................................................................................................................................................ 19
17   Seed smooth ¹ ............................................................................................................................. 2. - E. villosa Waldst. et Kit.
17* Seed netted or with irregular embossed folds ........................................................................................................................ 18
18   An annual plant. Leaves herbaceous, toothed .......................................................................................... 9. - E. helioscopia L.
18* Perennial plant. The leaves are thick, fleshy, entire .................................................................................. 10. - E. myrsinites L.
19   Perennials ............................................................................................................................................................................ 20
19* Annual plants ....................................................................................................................................................................... 30
20   The bracts of more than half fused in a round pan ............................................................................. 16. - E. amygdaloides L.
20* Bracts free ........................................................................................................................................................................... 21
21    Perianth glands whole, without horns ................................................................................................................................... 22
21* The glands of the perianth with horns ................................................................................................................................... 24
22   The styles longer than 1.8 mm; stem leaves finely serrated, up to 18 mm wide ……....................…….. 12. - E. nicaeensis All.
22* The styles shorter than 1.8 mm; stem leaves entire, up to 10 mm wide ………….....................................................……..... 23
23    Stem leaves herbaceous; the box is 2.0 - 2.4 mm long and 2.0 - 3.2 mm wide; the seed is 1.6 - 2.0 mm long and 0.5 - 1.5 mm
wide ......................................................................................................................................................... 14. - E. niciciana Borb.
23* Stem leaves leathery; the box is 2.4 - 4.0 mm long and 2.6 - 3.5 mm wide; the seed is 2.1 - 2.5 mm long and 1.0 - 1.2 mm wide ............................................................................................................................................................... 13. - E. seguerana Neck.
¹ Peculiarities can also be distinguished on immature seeds.
24   Stem leaves fleshy .................................................................................................................................... 15. - E. paralias L.
24* Non-fleshy stem leaves 25 ……………..................................................…………..…………………………………….. 25
25 Stem leaves (especially young and on the lower surface) densely short-ciliated ……….....................… 17. - E. salicifolia Host
25* Stem leaves bare ............................................. ................................................................................................................. 26
26   Stem leaves narrowly linear to awl-shaped, equally wide in length, 0.5 - 3.0 mm wide .................…… 20. - E. cyparissias L.
26* Stem leaves linear-lance to broadly elliptical, at the base or at the tip clearly enlarged, wider than 2 mm ............................... 27
27    Stem leaves with radiant veins, all veins coming from the base; appendage large, googled, up to 1/3 of the length of the seed ……....................................................................................................................................................... 11. - E. barrelieri Savi
27* Stem leaves with pinnate veins, lateral veins coming from the central one; the appendage warty, small, up to 1/10 of the length
of the seed .............................................................................................................................................................................. 28
28  The glands of the perianth with simple thin horns, the styles from the top of 1/4 - 1/3 bipartite, spatulate-shaped .................. 29
28* The glands of the perianth with thick horns, dilated at the apex, often 2-3 parts, the columns short, two-part, globularly thickened …………………….......................................................................................................................................... 21. - E. esula L.
29   Stem leaves gradually pointed to the top, dark green to blue-green, shiny; perianth glands with thin long horns ........................ …………...................................................................................................................................... 19. - E. lucida Waldst. et Kit.
29* Stem leaves obtuse, rarely pointed, gray-green to yellow-green; matte; glands of the perianth with very short horns ............... …………………………..............................................................................................………………... 18. - E: agraria M.V.
30 (19*) Seed on the surface with protruding granular or warty formations ............................................................................... 31
30* Seed on the surface with concave pits or furrows .............................................................................................................. 32
31   Seeds ovate-cylindrical to tetrahedral, 0.9 - 1.1 mm wide and 0.8 - 1.1 mm thick, with small granular formations, without
appendage ................................................................................................................................................... 25. - E. aleppica L.
31* The seed is ovoid, prismatic, 0.8 - 0.9 mm wide and 0.7 - 0.8 mm thick, with clear convex warty formations, the appendage
flattened membranous, easily deciduous ........................................................................................................... 23. - E. exigua L.
32   The seed is ovoid-cylindrical, evenly covered over the entire surface with more or less round pits ..... 24. - E. taurinensis All.
32* Seed elongated prismatic, on the surface with two or more furrows and round pits …................................................... … 33
33   Seed in cross section irregularly hexagonal, on the four dorsal planes with 4 - 5 round pits, on both front surfaces with one long
longitudinal groove ………….............................................................................................................……….. 26. - E. peplus L.
33* Seed in cross section drained rhombically, on both dorsal and especially on both front surfaces with (3) 4 - 6 (7) more or less
regular transverse grooves (top and main often reduced to pits) …...…………………………………………. 22. - E. falcata L.
Developed by B. Kuzmanov

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

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Euphorbia is a very large and diverse genus of flowering plants, commonly called spurge, in the spurge family (Euphorbiaceae). "Euphorbia" is sometimes used in ordinary English to collectively refer to all members of Euphorbiaceae (in deference to the type genus), not just to members of the genus.[2] Some euphorbias are commercially widely available, such as poinsettias at Christmas. Some are commonly cultivated as ornamentals, or collected and highly valued for the aesthetic appearance of their unique floral structures, such as the crown of thorns plant (Euphorbia milii). Euphorbias from the deserts of Southern Africa and Madagascar have evolved physical characteristics and forms similar to cacti of North and South America, so they (along with various other kinds of plants) are often incorrectly referred to as cacti.[3] Some are used as ornamentals in landscaping, because of beautiful or striking overall forms, and drought and heat tolerance.[4][5]
Euphorbias range from tiny annual plants to large and long-lived trees.[5] The genus has over[4] or about 2,000 members,[6] making it one of the largest genera of flowering plants.[7][8] It also has one of the largest ranges of chromosome counts, along with Rumex and Senecio.[7] Euphorbia antiquorum is the type species for the genus Euphorbia.[9] It was first described by Carl Linnaeus in 1753 in Species Plantarum.
The plants share the feature of having a poisonous, milky, white, latex-like sap, and unusual and unique floral structures.[4] The genus may be described by properties of its members' gene sequences, or by the shape and form (morphology) of its heads of flowers. When viewed as a whole, the head of flowers looks like a single flower (a pseudanthium).[4] It has a unique kind of pseudanthium, called a cyathium, where each flower in the head is reduced to its barest essential part needed for sexual reproduction.[4] The individual flowers are either male or female, with the male flowers reduced to only the stamen, and the females to the pistil.[4] These flowers have no sepals, petals, or other parts that are typical of flowers in other kinds of plants.[4] Structures supporting the flower head and other structures underneath have evolved to attract pollinators with nectar, and with shapes and colors that function in a way petals and other flower parts do in other flowers. It is the only genus of plants that has all three kinds of photosynthesis, CAM, C3 and C4.[4]

Description

The plants are annual, biennial or perennial herbs, woody shrubs, or trees with a caustic, poisonous milky 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 in) tall. The deciduous[citation needed] leaves may be 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.

Inflorescence and fruit

Like all members of the family Euphorbiaceae, spurges have unisexual flowers.
In Euphorbia, flowers occur in a head, called the cyathium (plural cyathia). Each male or female flower in the cyathium head has only its essential sexual part, in males the stamen, and in females the pistil. The flowers do not have sepals, petals, or nectar to attract pollinators, although other nonflower parts of the plant have an appearance and nectar glands with similar roles. Euphorbias are the only plants known to have this kind of flower head.[13]
Nectar glands and nectar that attract pollinators are held in the involucre, a cup-like part below and supporting the cyathium head. The "involucre" in the genus Euphorbia is not to be confused with the "involucre" in family Asteraceae members, which is a collection of bracts called phyllaries, which surround and encase the unopened flower head, then support the receptacle under it after the flower head opens.
The involucre is above and supported by bract-like modified leaf structures (usually in pairs)[citation needed] called cyathophylls', or cyathial leaves. The cyathophyll often has a superficial appearance of being petals of a flower.
Euphorbia flowers are tiny, and the variation attracting different pollinators, with different forms and colors occurs, in the cyathium, involucre, cyathophyll, or additional parts such as glands that attached to these.
The collection of many flowers may be shaped and arranged to appear collectively as a single individual flower, sometimes called a pseudanthium in the Asteraceae, and also in Euphorbia.
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 unfavorable conditions are male only, and only produce female flowers in the cyathia with maturity or as growing conditions improve.[citation needed]
The female flowers reduced to a single pistil usually split into three parts, often with two stigmas at each tip.[citation needed] Male flowers often have anthers in twos.[citation needed] Nectar glands usually occur in fives,[14] may be as few as one,[14] and may be fused into a "U" shape.[13] The cyathophylls often occur in twos, are leaf-like, and may be showy and brightly coloured and attractive to pollinators, or be reduced to barely visible tiny scales.[citation needed]
The fruits are three- or rarely two-compartment capsules, sometimes fleshy, but almost always ripening to a woody container that then splits open, sometimes explosively. The seeds are four-angled, oval, or spherical, and some species have a caruncle.[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

SPECIES:

Euphorbia amygdaloides L. - Wood spurge

Euphorbia cyparissias L. - Cypress spurge

Euphorbia esula L. - Green spurge, Leafy spurge

Euphorbia helioscopia L. - Sun spurge

Euphorbia palustris L. - Marsh spurge, Marsh euphorbia

Euphorbia plathyphillos L. - Broad leaves spurge

Euphorbia virgata Waldst. et Kit. - Upright milk

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