Swietenia
| Swietenia | ||||||||||||
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Habit of Swietenia mahogany |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Swietenia | ||||||||||||
| Jacq. |
Swietenia is a genus of plants fromthe mahogany family (Meliaceae). The three species occurnaturallyonly in the Neotropic . All three types provide valuable commercial timbers.
description
Appearance and leaves
The Swietenia species grow as deciduous trees . The wood is red in color. The alternate and spiral leaves on the branches are pinnate in pairs. The leaflets on the rhachis are more or less opposite to each other. There are no stipules . There are many small extra-floral nectaries on the rachis, on the petioles, and on the leaflets.
Inflorescences and flowers
The lateral or almost terminal inflorescences have the shape of a thyrsus . The relatively small flowers are unisexual and four or five-fold with a double flower envelope . The five small sepals are fused to about half of their length. The rarely four, usually five free petals are wide. The seldom eight or usually ten stamens are fused tubular, with seldom eight or usually ten (pointed) lobes and rarely eight or usually ten anthers in between, which are inserted on the inside of the stamen. The discus is ring-shaped. The egg-shaped ovary is rare four or six, mostly fünfkammerig. Each ovary chamber contains 9 to 16 pendent ovules . The cylindrical stylus ends in a disc-shaped, multi-lobed scar. There are pestillodes (sterile pistils) in the male flowers and staminodes (sterile stamens) in the female flowers.
Fruits and seeds
The woody capsule fruits are elongated or egg-shaped and usually five-fan. In each fruit compartment, several seeds per fruit compartment hang with the wing end on the upper end of the angular columnella. The winged seeds have a more or less fleshy endosperm and an embryo with two thin cotyledons ( cotyledons ) and a very short Radicula.
Systematics
The genus Swietenia was established in 1760 by Nikolaus Joseph von Jacquin in Enumeratio Systematica Plantarum, quas in insulis Caribaeis , 20. The type species is Swietenia mahagoni (L.) Jacq. The generic name Swietenia honors Gerard van Swieten . Synonyms for Swietenia are: Elutheria M.Roem. , Mahogany Adans. , Roia Scop. , Suitesia Stokes orth. Var.
There are only three types of Swietenia :
- Swietenia humilis Zucc. : It occurs from western and southern Mexico through northwestern Costa Rica , El Salvador , Guatemala and Honduras to Nicaragua .
- American mahogany ( Swietenia macrophylla King ): The natural range extends from Mexico (Veracruz, Campeche, Chiapas, Quintana Roo, Tabasco) over Belize , Costa Rica, Guatemala, Honduras, Nicaragua, Panama to French Guiana , Venezuela and Brazil and Bolivia to to Peru (Huanuco, Loreto, San Martin). It occurs wild in some tropical countries.
- Swietenia mahagoni (L.) Jacq. : Its natural range in the Caribbean includes: Florida , the Bahamas , Cuba , Hispaniola and Jamaica. The species is feral on other Caribbean islands.
There are two naturally occurring hybrids : One is a cross product between Swietenia macrophylla and Swietenia humilis , it was found in the overlapping area of their distribution areas. The other, called Swietenia × aubrevilleana , was created on plantations with both species from Swietenia macrophylla and Swietenia mahogani .
use
The wood from Swietenia macrophylla is traded under the trade names: American mahogany , real mahogany , Honduras, Tabasco, Nicaragua mahogany (in German-speaking countries); caoba (Central America); aguano (Panama, Peru, Brazil); orura (Venezuela); zopilote (Mexico); sapoton (Suriname); yulu (Nicaragua); crura (Bolivia); acajou d'Amérique (in French-speaking countries); American mahogani , baywood (Great Britain); broadleaf mahagony (USA). All three species are protected by CITES : Swietenia humilis and Swietenia mahagoni in Annex II, and Swietenia macrophylla in Annex III for Costa Rica.
swell
- Hua Peng & David J. Mabberley: Swietenia in der Flora of China , Volume 11, 2008, p. 111: Online. (Section description and systematics)
- Fernando Patiño Valera: Genetic Resources of Swietenia and Cedrela in the Neotropics : The genus Swietenia at FAO, 1997 (section systematics)
Individual evidence
- ↑ NR Lersten, SR Rugenstein: Foliar nectaries in Mahogany (Swietenia Jacq.) In: Annals of Botany. Volume 49, Issue 3, 1982, pp. 397-401, doi: 10.1093 / oxfordjournals.aob.a086263 .
- ↑ First publication scanned at biodiversitylibrary.org .
- ^ A b Swietenia in the Germplasm Resources Information Network (GRIN), USDA , ARS , National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland.
- ^ Swietenia at Tropicos.org. Missouri Botanical Garden, St. Louis
- ↑ Entry in Handelshölzer by HG Richter & MJ Dallwitz.
