Machaerium scleroxylon

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Machaerium scleroxylon
Systematics
Order : Fabales (Fabales)
Family : Legumes (Fabaceae)
Subfamily : Butterflies (Faboideae)
Tribe : Dalbergieae
Genre : Machaerium
Type : Machaerium scleroxylon
Scientific name
Machaerium scleroxylon
Tul.

Machaerium scleroxylon is a species of the genus Machaerium within the legume family (Fabaceae). Machaerium scleroxylon is found in western, southern and central Brazil, Paraguay , northern Argentina and Bolivia . It is also known as Caviúna or Santos rosewood , although it is actually not rosewood . Only a few species from the genus Dalbergia are referred toas rosewood.

description

Vegetative characteristics

Machaerium scleroxylon grows as a deciduous tree and reaches stature heights of up to 30 meters and trunk diameters of up to 90 centimeters. It forms a dense crown. The trunk is fluted at the bottom. The gray-brownish bark flakes off in plates. The young branches have many spines .

The alternate leaves arranged on the branches are divided into a petiole and a leaf blade. The imparipinnate leaf blade has a hairy rachis and is up to 11 centimeters long and has 9 to 16 leaflets. The short-stalked leaflets are egg-shaped to obovate or elliptical with a length of up to 3 centimeters and a width of up to 1 centimeter. The upper end of the leaflets is rounded to indented and partly set off, articulated, the edges are whole. They are lighter on the underside and slightly hairy. There are thorny stipules .

Generative characteristics

The terminal and lateral, racemose or paniculate inflorescences have a hairy rachis and contain many sessile flowers. There are thorny bracts . There are patchy, hairy propsheets .

The hermaphrodite flowers are zygomorphic and five-fold with a double flower envelope . The five sepals with velvety purple hairs on the outside are fused together like a bell. Five calyx teeth can be seen. The velvety crown has the shape of a typical butterfly flower and is hairy in white, cream and purple. The ten stamens are monadalphic. There is a cushion-shaped disc . The stalked ovary is finely haired.

The brownish wing nuts (Samara) are 5 to 6 centimeters long and contain only one seed. The seeds are kidney-shaped and flattened with a length of up to 10 millimeters.

Taxonomy

The first description of Machaerium scleroxylon was made in 1844 by Edmond Tulasne in Archives du Muséum d'Histoire Naturelle, Paris. Tome IV, Sirou, 1844, pp. 92-93.

Wood

The reddish, medium to heavy and hard, durable wood of the Santos rosewood is not used as real rosewood, but as a substitute for the protected Rio rosewood . It is also known as Bolivian or Santos rosewood or Pau Ferro and Morado , Kayenne or Cayenne rosewood .

Allergenic effect

Allergologically significant ingredients of wood are the ( R ) -2,3-dimethoxy-5- (1-phenyl-2-propenyl) -2,5-cyclohexadiene-1,4-dione [( R ) -3,4-dimethoxydalbergione ] and its hydroquinone , which can be contained in total concentrations of 1.4–6.1% or 1.2–4.9%.

Sensitization occurs after contact with wood dust or with solid wood. Concentrations of more than 1% 3,4-dimethoxydalbergione in wood can primarily cause toxic dermatitis and sensitize people even after a single contact.

  • Solid wood

  • Santos veneer

  • ( R ) -3,4-dimethoxydalbergione C 17 H 16 O 4

literature

  • Carlos Toledo Rizzini: Árvores e madeiras úteis do Brasil: manual de dendrologia brasileira. 2ª Edição, 8ª Reimpressão, Blucher, 2019, ISBN 978-85-212-0051-2 , p. 161 f.
  • M. Joaquín Justiniano, Todd S. Fredericksen: Ecología y Silvicultura de Especies Menos Conocidas - Morado Machaerium scleroxylon Tul. Fabaceae. Proyecto de Manejo Forestal Sostenible (BOLFOR), Santa Cruz de la Sierra, Bolivia 1998, online (PDF; 1.3 MB).
  • JF Toledo: Arquivos de botânica do Estado de Saõ Paulo. Nova Series, Volume III, Fasc. I, 1952, p. 237 ff.
  • Julio S. Inglez Sousa et al .: Enciclopédia agrícola brasileira. C-D 2, EDUSP, 1998, ISBN 85-31404-60-6 , pp. 246 f.
  • Machaerium scleroxylon. In: Rodriguésia - Revista do Jardim Botânico do Rio de Janeiro. Volume 58, Issue 2, 2007, pp. 306–309, online (PDF; 31.5 MB), BNDigital, accessed on October 26, 2018.

Web links

Commons : Machaerium scleroxylon  - collection of images, videos and audio files

Individual evidence

  1. ↑ Machaerium scleroxylon at KEW Science, accessed on October 26, 2018.
  2. ↑ Machaerium scleroxylon in the Germplasm Resources Information Network (GRIN), USDA , ARS , National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland. Retrieved October 31, 2018.
  3. ^ A b Edmond Tulasne : Archives du Muséum d'Histoire Naturelle, Paris. Tome IV, Sirou, 1844, pp. 92-93 online at biodiversitylibrary.org, accessed October 26, 2018.
  4. ^ J. Roed-Petersen, T. Menné, KM Nielsen, N. Hjorth: Is it possible to work with Pao ferro (Machaerium scleroxylum, Tul.)? In: Archives of Dermatological Research. Volume 279, 1987, pp. 108-110, doi: 10.1007 / BF00585932 .
  5. ^ BM Hausen: Current contact allergens. In. Allergology. 6, 1983, pp. 194-197.
  6. ^ KH Schulz, I. Garbe, BM Hausen, MH Simatupang: The sensitizing capacity of naturally occuring quinones. Experimental studies in guinea pigs. II. Benzoquinones. In: Archives of Dermatological Research. Volume 264, 1979, pp. 275-286, PMID 464645 .
  7. ↑ BM Hausen: Frequency and significance of toxic and allergic contact dermatitis due to Machaerium scleroxylum Tul. (Pao ferro), a substitute wood for rosewood (Dalbergia nigra All.). In: dermatologist. Volume 33, 1982, pp. 321-328.
  8. ^ HI Maibach: Active sensitization to wood extracts. In: Contact Dermatitis Newsletter. Volume 7, 1970, p. 149.
  9. ↑ JWW Morgan, RJ Orsler, DS Wilkinson: dermatitis due to wood dusts of Khaya anthotheca and Machaerium scleroxylon. In: British Journal of Industrial Medicine. Volume 25, 1968, pp. 119-125, PMC 1008719 (free full text).
  10. ^ WB Eyton, WD Ollis, M. Fineberg, OR Gottlieb, I. Salignac de Souza Guimarães, M. Taveira Magalhães: The neoflavanoid group of natural products - II .: The examination of Machaerium scleroxylon and some biogenetic proposal regarding the neoflavanoids. In: Tetrahedron. Volume 21, Issue 9, 1965, pp. 2697-2705.