''Cryptostegia'' is a genus of

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

s native to

tropical Africa Although tropical Africa is mostly familiar to the West for its rainforests, this biogeographic realm of Africa is far more diverse. While the tropics are thought of as regions with hot moist climates, which are caused by latitude and the tropi ...

and

Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa ...

. The genus is 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 the ...

Description

''Cryptostegia'' includes three species of slender, many-stemmed, woody, perennial

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 themselv ...

s. When their stems or leaves are damaged they exude a milky latex that is extremely toxic to livestock; it contains

cardiac glycosides 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 co ...

that cause sudden death, especially after violent exertion. Though the latex is of good quality it is not used commercially. ''Cryptostegia'' are

evergreen In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This also pertains to plants that retain their foliage only in warm climates, and contrasts with deciduous plants, which ...

and are grown for their showy ornamental vines. They are vigorous and self-supporting and their vines sometimes attain a length of 15m. Leaves are ovate, opposite, glossy and dark green. They are 6–10 cm long and 3–5 cm wide. Clusters of large, showy, funnel-shaped flowers with 5 white to rose-pink or reddish-purple petals bloom in summer after the wet season. Seed pods are rigid 10–12 cm long and 3–4 cm wide, and grow in pairs at the end of a short stalk. The seeds are attached to a silky white floss. The plants grow rampantly in a favourable climate and are invasive in some areas. In

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

''Cryptostegia grandiflora'' in particular has been declared a Weed of National Significance. It is regarded as one of the worst weeds in Australia because of its invasiveness, potential for spread, and economic and environmental impacts.Weeds of National Significance Department of the Environment and Heritage and the CRC for Australian Weed Management, 2003 In cultivation, the plants require a hot climate.

Image Gallery

File:Cryptostegia at Padnekad.jpg, Cryptostegia File:Cryptostegia buds at Padnekad in Kasaragod.jpg, Cryptostegia buds File:Cryptostegia leaves at padnekad in kerala.jpg, Cryptostegia leaves File:Cryptostegia plant at padnekad.jpg, Cryptostegia plant

Species

*''

Cryptostegia grandiflora ''Cryptostegia grandiflora'', commonly known as rubber vine, is a woody-perennial vine that is native to south-west Madagascar. It is also a significant weed in northern Australia, sometimes regarded as the worst weed in all of Australia. It ...

'' R.Br. – rubber vine, purple allamanda *''

Cryptostegia madagascariensis ''Cryptostegia madagascariensis'' is a species of flowering plant in the family Apocynaceae. It is commonly known as purple rubber vine, is a woody-Perennial plant, perennial vine that is native to western and northern Madagascar. It has also bee ...

'' Bojer ex Decne. – purple rubber vine

References

External links

Botanica Sistematica
* * Apocynaceae genera Periplocoideae Taxa named by Robert Brown (botanist, born 1773) {{Apocynaceae-stub