Mitragyna

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Mitragyna
Mitragyna parviflora

Mitragyna parviflora

Systematics
Euasterids I
Order : Enzianartige (Gentianales)
Family : Red family (Rubiaceae)
Subfamily : Cinchonoideae
Tribe : Naucleeae
Genre : Mitragyna
Scientific name
Mitragyna
Korth.

Mitragyna is a plant genus in the family of the redness plants (Rubiaceae). Six species are distributed in Asia and Malesia and four species are found in Africa (as of Löfstrand et al. 2014).

description

Upper and lower side of the leaf of Mitragyna speciosa
Opposite, stalked, simple leaves and stipules of Mitragyna tubulosa
Illustration of Mitragyna diversifolia
Branches with stalked, single leaves and spherical inflorescences of Mitragyna parviflora
Illustration atlas of tree species of Java , figure 513 from Mitragyna diversifolia

Appearance and leaves

Mitragyna species grow as small to fairly large trees, which are mostly deciduous in the dry season .

The opposite arranged leaves are divided into petioles and leaf blades and sometimes have domatia . The papery to leathery leaf blades are simple. The young leaves, at least the midrib and sometimes the stipules are occasionally reddish to reddish-purple in color. The sloping, interpetiolaren Stipules are simple, ovate to obovate, sometimes keeled and often large and well developed; they stand upright and pressed together by the flattened buds.

Inflorescences and flowers

In on the main trunk or on the branches terminally, sometimes for a short inflorescence stem, frets that time, zymösen , doldigen or tyrsusförmigen total inflorescences are spherical, kopfige together are part of inflorescences. Often there are reduced, corolla-like and / or bract-like leaves and always enlarged, sometimes conspicuously colored, non-durable stipules on the inflorescences. The bracts are spatulate to inverted pyramidal.

The more or less sedentary flowers are hermaphrodite, zygomorphic and five-fold with a double flower envelope . The five sepals are fused to a trimmed or five-toothed calyx depending on the species. The five cream-colored to yellow-green petals are fused together funnel-shaped or closely shaped like a salver. The corolla tube is glabrous to variable on the inside, particularly hairy on the throat. The five corolla lobes are ascending in the open flower. There is a circle with five fertile stamens . The stamens inserted on or just below the throat of the corolla tube are short and the anthers partially or completely protrude beyond the corolla tube. Two carpels are at a two-chambered ovary grown. There are many ovules per ovary chamber , which are arranged on a fleshy hanging placenta in the upper third of the septum. The stylus ends in a club- to cap-shaped scar that protrudes over the corolla tube.

Infructescence, fruits and seeds

The spherical fruit heads contain capsule fruits around which the calyx is sometimes retained. The obovate to ellipsoidal, cartilaginous to woody capsule fruits contain many seeds. The small seeds are flattened and spindle-shaped to lanceolate. The seeds have short wings at both ends, the basal wing sometimes having two columns or notches.

Bark of Mitragyna parviflora

Systematics and distribution

The genus Mitragyna was established in 1839 by Pieter Willem Korthals in Observationes de Naucleis Indicis , p. 19. Synonyms for Mitragyna Korth. nom. cons. are: Bamboga Baill. orth. var., Mamboga Blanco , Paradina Pierre ex Pit. , Stephegyne Korth. Colin E. Ridsdale created a systematic review in 1978, A revision of Mitagyna and Uncaria (Rubiaceae). In: Blumea , Volume 24, pp. 43-100, and the African species in the genus Hallea Leroy , which by Y.-F. Deng: Fleroya, a substitute name for Hallea J.-F. Leroy (Rubiaceae). In: Taxon , Volume 56, 2007, pp. 247-248 became the synonym of Fleroya Y.F.Deng . Many subsequently created floral works and works on the subfamily and the tribe integrate the African species Mitragyna inermis into the genus. The genus Mitragyna belongs to the tribe Naucleeae in the subfamily Cinchonoideae within the Rubiaceae family . Löfstrand et al. However, 2014 showed that all Fleroya species belong to Mitragyna .

Six Mitragyna species are found in Asia and Malesia . Three species are native to China and four species are native to Thailand. Mitragyna inermis and since Löfstrand et al. In 2014 another three occur in Africa.

There are six to ten types of Mitragyna :

use

Some species, such as Mitragyna diversifolia , are used to produce wood .

The ( medicinal ) drug "Kratom" is obtained from the leaves of Mitragyna speciosa . The leaves are also used to make tea, chew and smoke. In Thailand and Malaysia the leaves are used in folk medicine . The main active ingredient is the alkaloid Mitragynine , which is only known as an ingredient in Mitragyna speciosa ; it is said to have a stimulating effect in low doses and narcotic in high doses .

swell

  • Tao Chen, Charlotte M. Taylor: Mitragyna . Rubiaceae. In: Flora of China Editorial Committee: Wu Zheng-yi, Peter H. Raven, Deyuan Hong (Eds.): Flora of China . Cucurbitaceae through Valerianaceae, with Annonaceae and Berberidaceae. Volume 19. Science Press and Missouri Botanical Garden Press, Beijing and St. Louis 2011, ISBN 978-1-935641-04-9 , pp. 218–219 (English, " Mitragyna - Online " - online text is identical to the printed work; printed work - full text online). (Sections description, distribution, use and systematics)
  • S. Nazimuddin, M. Qaiser: Rubiaceae in the Flora of Pakistan : Mitragyna at Tropicos.org. In: Flora of Pakistan . Missouri Botanical Garden, St. Louis (Description and Distribution Sections)
  • Christian Puff, from 2007: Flora of Thailand : Rubiaceae - Mitragyna . (Sections Description and Distribution)

Individual evidence

  1. ^ Mitragyna at Tropicos.org. Missouri Botanical Garden, St. Louis
  2. ^ Mitragyna on the Germplasm Resources Information Network (GRIN), USDA , ARS , National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland. Retrieved October 18, 2017.
  3. ↑ Stefan D. Löfstrand, Åsa Kruger, Sylvain G. Razafimandimbison, Birgitta Bremer: Phylogeny and generic delimitation in the sister tribes Hymenodictyeae and Naucleeae (Rubiaceae). In: Systematic Botany , Volume 39, Issue 1, 2014, pp. 304-315. doi : 10.1600 / 036364414X678116
  4. ↑ a b c d e f g h i j k Rafaël Govaerts, 2003: World Checklist of Selected Plant Families Database in ACCESS: 1-216203. The Board of Trustees of the Royal Botanic Gardens. Rafaël Govaerts (Ed.): Mitragyna. In: World Checklist of Selected Plant Families (WCSP) - The Board of Trustees of the Royal Botanic Gardens, Kew . Retrieved October 18, 2017.
  5. ↑ a b Tao Chen, Charlotte M. Taylor: Mitragyna . Rubiaceae. In: Flora of China Editorial Committee: Wu Zheng-yi, Peter H. Raven, Deyuan Hong (Eds.): Flora of China . Cucurbitaceae through Valerianaceae, with Annonaceae and Berberidaceae. Volume 19. Science Press and Missouri Botanical Garden Press, Beijing and St. Louis 2011, ISBN 978-1-935641-04-9 , pp. 218–219 (English, " Mitragyna - Online " - online text is identical to the printed work; printed work - full text online).

Web links

Commons : Mitragyna  - collection of images, videos and audio files