''Strophanthus'' is a genus of flowering plants in the family

Apocynaceae Apocynaceae (from ''Apocynum'', Greek for "dog-away") is a family of flowering plants that includes trees, shrubs, herbs, stem succulents, and vines, commonly known as the dogbane family, because some taxa were used as dog poison Members of ...

, first described as a genus in 1802. It is native primarily to tropical

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

, extending to

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. It is bounded to the south by of coastline that stretch along the Atlantic Ocean, South Atlantic and Indian Oceans; to the ...

, with a few species in

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an are ...

from southern

India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...

New Guinea New Guinea (; Hiri Motu: ''Niu Gini''; id, Papua, or , historically ) is the world's second-largest island with an area of . Located in Oceania in the southwestern Pacific Ocean, the island is separated from Australia by the wide Torr ...

and southern China. The genus name is a compound of the Greek words στροφος (''strophos'') "twisted" and ανθοσ (''anthos'') "flower", in reference to the corolla lobes which, in some species - notably ''S. petersianus'' (see below) - resemble long twisted ribbons or threads and can reach a length of 30–35 cm. This trait, in addition to colouring involving combinations of bright pinks, purples and oranges, combine to make the flowers among the most ornamental in the plant kingdom. The genus includes

vine A vine (Latin ''vīnea'' "grapevine", "vineyard", from ''vīnum'' "wine") is any plant with a growth habit of trailing or scandent (that is, climbing) stems, lianas or runners. The word ''vine'' can also refer to such stems or runners themsel ...

s, shrubs, and small

tree In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are ...

s. The leaves are opposite or whorled, simple broad lanceolate, 2–20 cm long, with an entire margin. Several African tribes used ''Strophanthus'' as the principal ingredient in

arrow poison Arrow poisons are used to poison arrow heads or darts for the purposes of hunting and warfare. They have been used by indigenous peoples worldwide and are still in use in areas of South America, Africa and Asia. Notable examples are the poisons se ...

. After dipping the arrows of their hunting weapons into a strong concentration of the ingredient, the effect was to stun their prey. Plants from this genus produce toxic

alkaloid Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar ...

s and

cardiac glycoside Cardiac glycosides are a class of organic compounds that increase the output force of the heart and decrease its rate of contractions by inhibiting the cellular sodium-potassium ATPase pump. Their beneficial medical uses are as treatments for c ...

s g-

strophanthin Strophanthins are cardiac glycosides in plants of the genus ''Strophanthus''. The singular may refer to: * g-Strophanthin, also known as ouabain * k-Strophanthin It is commonly used in euthanasia (lethal injections) See also

* Cardenolide {{C ...

(syn. ouabain), k-

* Cardenolide {{C ...

, and e-

* Cardenolide {{C ...

. As ordinarily administered, the drug acts on the heart before influencing any other organ or tissue. Indeed, often no other effect may be observed. Some of the chemicals in the plants are used to produce the drug ouabain, which was taken as a cardiac stimulant to treat heart failure and sometimes g-strophanthin is advocated as an alternative treatment to more contemporary practices. The effect is similar to that of the drug digoxin, which is produced from ''

Digitalis purpurea ''Digitalis purpurea'', the foxglove or common foxglove, is a poisonous species of flowering plant in the plantain family Plantaginaceae, native to and widespread throughout most of temperate Europe. It has also naturalised in parts of North Am ...

''.

Gallery

Flowers

File:Strophanthus amboensis 1DS-II 3-1571.jpg, '' Strophanthus amboensis'' File:Corckscrew Tree.jpg, '' Strophanthus boivinii'' File:Strophanthus dichotomus Decne.; flowering branch with separa Wellcome V0042705.jpg , '' Strophanthus caudatus'' (coloured plate) File:Strophanthus divaricatus2.jpg, ''

Strophanthus divaricatus ''Strophanthus divaricatus'' is a liana or sarmentose shrub that can grow up to tall, with a trunk diameter of up to . ''Divaricatus'' is from the Latin meaning "spreading at a wide angle". The plant has been used medicinally: as a heart stim ...

'' File:Strophanthus gratus 16.jpg, '' Strophanthus gratus'' File:Strophanthus hispidus - Köhler–s Medizinal-Pflanzen-131.jpg, ''

Strophanthus hispidus ''Strophanthus hispidus'', the hispid strophanthus, (family: Apocynaceae) is a liana or shrub that can grow up to tall. Its flowers feature a yellow corolla and yellow corona lobes spotted with red, purple or brown. The seeds, like those of sev ...

'' (coloured plate) File:Strophanthus kombe00.jpg, ''

Strophanthus kombe ''Strophanthus kombe'', the kombe arrow poison, is a vine that grows in the tropical regions of Eastern Africa, and is part of the genus ''Strophanthus'', which contains approximately 38 species. ''S. kombe'' contains a cardiac glycoside which d ...

'' (botanical drawing) File:Strophanthus petersianus 1DS-II 3-2770.jpg, '' Strophanthus petersianus'' File:Strophanthus preussii (25433002894).jpg, '' Strophanthus preussii'' File:Strophanthus sarmentosus 0002.jpg, '' Strophanthus sarmentosus'' File:Strophanthus speciosus 1DS-II 6026.jpg, '' Strophanthus speciosus'' ;Species ;formerly included in genus * ''Strophanthus aambe = Papuechites aambe'' * ''Strophanthus balansae = Anodendron paniculatum'' * ''Strophanthus jackianus = Wrightia dubia''

References

External links

Apocynaceae genera Poisonous plants {{Apocynaceae-stub