Acanthus (genus)

Acanthus
	Acanthus montanus
Systematics
	Asterids
	Euasterids I
Order :	Mint family (Lamiales)
Family :	Acanthus family (Acanthaceae)
Subfamily :	Acanthoideae
Genre :	Acanthus
Scientific name
	Acanthus
	L.

Acanthus ( Acanthus ) is a plant genus within the family of the Acanthaceae (Acanthaceae). The 20 to 30 species are mainly found in tropical to subtropical areas of the Old World . Another common name is "Bärenklau". However, it should not be confused with the genus hogweed ( Heracleum ).

The foliage is the template of the art-historically significant acanthus ornament .

Description and ecology

Illustration of the true hogweed ( Acanthus mollis )

True hogweed inflorescence ( Acanthus mollis )

Appearance and leaves

Acanthus species usually grow as perennial herbaceous plants and a few as subshrubs . The vegetative reproduction by means of rhizomes plays a major role in many acanthus species. Some species, such as the true hogweed ( Acanthus mollis ), can form dense populations in this way. The shoot axes are independently upright to prostrate. The opposite, or rarely whorled to basal heaped leaves are divided into petiole and leaf blade. The leaf blades are simple to pinnate. The leaf margin is smooth, lobed or toothed to thorny.

Inflorescences and flowers

The seldom lateral, mostly terminal, variously shaped , interrupted, spiked inflorescences are 0.40 to 2 meters high. The egg-shaped bracts overlap like roof tiles, have a prickly edge and enlarge until the fruit is ripe. The flowers are usually above two thorn-reinforced bracts , which often surround the flower like a collar ; they can be absent. The hermaphrodite flowers are zygomorphic and rarely three, mostly four-fold with a double flower envelope . The four sepals are fused together and the calyx ends in unequal calyx lobes of which the lower and upper are longer and the lateral ones are shorter. The petals of most species are white to pink in color, there are also yellow ( Acanthus hirsutus ), blue and scarlet flowering species. The upper lip is sometimes reduced. The lower lip is enlarged and ends in three blunt corolla lobes. The four petals are only short tubular and the corolla ends with two lips. There is only one circle with four fertile stamens , they stand together in pairs and can be free or grown together. The thickened, robust stamens are inserted at the upper end of the corolla tube. The anthers consist of only one linear, elongated counter, which is mostly bearded with hair. Two carpels are an above-permanent, two-chambered ovary grown. There are only two ovules in each ovary chamber . The slim stylus ends in a two-column scar. The pollination is effected by insects ( Entomophilie ).

Fruits and seeds

The shiny, ellipsoidal, double-sided capsule fruits contain two to four seeds . The septum flaps hurl the seeds away when the capsule fruit is fully ripe. The seeds are more or less flattened.

Acanthus ebracteatus inflorescence

Acanthus hungaricus inflorescence

Acanthus ilicifolius inflorescences

Acanthus spinosus

Habit, leaves and inflorescences of Acanthus syriacus

Systematics and distribution

The first publication of Acanthus was made in 1753 by Carl Linnaeus . The genus name Acanthus is derived from the ancient Greek Akanthos (ὁ ἄκανθος "the thorny") with a Latinized ending. Synonyms for Acanthus L. are Cheilopsis Moq. and Acanthodus Raf. The genus Acanthus belongs to the tribe Acantheae in the subfamily Acanthoideae within the family of Acanthaceae .

The 20 to 30 species are mainly found in tropical to subtropical areas of the Old World . Few species occur in the warm, temperate areas of the Mediterranean. The centers of biodiversity are the Mediterranean and Asia .

There are 20 to 30 species of Acanthus :

Acanthus arboreus Forssk. : It only occurs in Egypt .
Acanthus austromontanus Vollesen
Acanthus carduaceus handle.
Acanthus caudatus Lindau
Acanthus dioscoridis L.
Acanthus ebracteatus Vahl : It thrives on the coasts of the Chinese provinces of Guangdong and Hainan and of Cambodia , India , Myanmar , Thailand , Vietnam , Indonesia , Papua New Guinea , Australia and the Pacific Islands.
Acanthus eminens C.B. Clarke : It occurs in Ethiopia , Sudan , Kenya and Uganda .
Acanthus flexicaulis Bremek.
Acanthus gaed Lindau
Acanthus greuterianus Snogerup, B. Snogerup & Strid
Acanthus guineensis Heine & P.Taylor
Acanthus hirsutus Boiss. : It occurs on islands in the Aegean Sea and in European and Asian Turkey .
Acanthus hungaricus ( Borbás ) Baen. (Syn .: Acanthus balcanicus Heywood & I.Richardson , Acanthus longifolius Host )
Acanthus ilicifolius L. (Syn .: Acanthus ebracteatus var. Xiamenensis (RTZhang) CYWu & CCHu , Acanthus ilicifolius var. Xiamenensis (RTZhang) YFDeng, NHXia & HengB.Chen , Acanthus xiamenensis R.T.Zhang ): It thrives on the coasts of Sri Lanka , India, Myanmar, Cambodia, Thailand, China, Vietnam, Malaysia, Indonesia, the Philippines, Papua New Guinea, Australia and the Pacific Islands.
Acanthus kulalensis Vollesen
Acanthus latisepalus C.B. Clarke
Acanthus leucostachyus Wall. ex Nees : It is common in India, Laos , Myanmar, Thailand, Vietnam and in the Chinese province of Yunnan .
Acanthus longibracteatus short
Acanthus mayaccanus Büttner
True hogweed ( Acanthus mollis L. ): There are about two subspecies:
- Acanthus mollis L. subsp. mollis : It occurs in France, Corsica , Italy and Morocco.
- Acanthus mollis subsp. platyphyllus Murb. (Syn .: Acanthus pubescens Engl. , Acanthus polystachyus Delile ): It occurs in Morocco, Algeria, Tunisia and Spain.
Acanthus montanus T.Anderson : It thrives in the mountainous regions of West Africa and in Angola.
Acanthus polystachyus Delile
Acanthus sennii Chiov.
Acanthus seretii De Wild.
Acanthus spinosus L .: It occurs in Italy, Croatia, Albania, Greece, Bulgaria, Algeria and Turkey.
Acanthus syriacus Boiss. : It occurs in Turkey, Syria, Lebanon and Israel.
Acanthus ueleensis De Wild.
Acanthus villaeanus De Wild.
Acanthus volubilis Wall.

use

Some species, particularly Acanthus hungaricus , Acanthus spinosus, and Acanthus mollis , are used as ornamental plants .

swell

Jia-qi Hu, Thomas F. Daniel: Acanthus L. , p. 379 - online with the same text as the printed work , In: Wu Zheng-yi, Peter H. Raven, Deyuan Hong (ed.): Flora of China. Volume 19: Cucurbitaceae through Valerianaceae, with Annonaceae and Berberidaceae , Science Press and Missouri Botanical Garden Press, Beijing and St. Louis, 2011, ISBN 978-1-935641-04-9 . (Sections Description and Systematics)
HR Coleman: Acanthus. In: Western Australian Herbarium (Ed.): FloraBase - The Western Australian Flora. Department of Environment and Conservation, 2008. (Section Description)

Individual evidence

↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p Jia-qi Hu, Thomas F. Daniel: Acanthus L. , p. 379 - online with the same text as the printed work , In: Wu Zheng-yi, Peter H Raven, Deyuan Hong (Ed.): Flora of China. Volume 19: Cucurbitaceae through Valerianaceae, with Annonaceae and Berberidaceae , Science Press and Missouri Botanical Garden Press, Beijing and St. Louis, 2011, ISBN 978-1-935641-04-9 .
↑ Carl von Linné: Species Plantarum. Volume 2, Lars Salvius, Stockholm 1753, p. 639 (“939”), digitized
↑ ^a ^b ^c ^d ^e ^f ^g Acanthus in the Germplasm Resources Information Network (GRIN), USDA , ARS , National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland.
↑ ^a ^b ^c ^d K. Marhold, 2011: Acanthaceae. : Datasheet Acanthus. at Euro + Med Plantbase - the information resource for Euro-Mediterranean plant diversity .

literature

Paul Wagler : Akanthos 9 . In: Paulys Realencyclopadie der classischen Antiquity Science (RE). Volume I, 1, Stuttgart 1893, Col. 1148-1150.

Web links

Commons : Akanthus ( Acanthus ) - collection of images, videos, and audio files

[FoC-1] ↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p Jia-qi Hu, Thomas F. Daniel: Acanthus L. , p. 379 - online with the same text as the printed work , In: Wu Zheng-yi, Peter H Raven, Deyuan Hong (Ed.): Flora of China. Volume 19: Cucurbitaceae through Valerianaceae, with Annonaceae and Berberidaceae , Science Press and Missouri Botanical Garden Press, Beijing and St. Louis, 2011, ISBN 978-1-935641-04-9 .

[SpPl-2] Carl von Linné: Species Plantarum. Volume 2, Lars Salvius, Stockholm 1753, p. 639 (“939”), digitized

[GRIN-3] ↑ ^a ^b ^c ^d ^e ^f ^g Acanthus in the Germplasm Resources Information Network (GRIN), USDA , ARS , National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland.

[Euro+Med-4] K. Marhold, 2011: Acanthaceae. : Datasheet Acanthus. at Euro + Med Plantbase - the information resource for Euro-Mediterranean plant diversity .