Thismiaceae

The Thismiaceae are a plant family of the order Yamswurzelartigen ( Dioscoreales ) within the monocot plants. There are mykotrophe and chlorophyll -free plants.

  • 3.1 Notes and references

Description

Habitus and sheets

All species of the family are mykotrophe and chlorophyll loose, perennial herbaceous plants. They are branched, coral -like rhizomes as outlasting. The opposite, alternate and distichous arranged leaves are parallel-veined, membranous, simple, small and sessile, or reduced to scales, with smooth leaf margins. The stomata are anomocytic.

Inflorescences and flowers

The flowers are borne with bracts individually or in racemose inflorescences. The radial symmetry to zygomorphic flowers are triple and hermaphrodite. There are two circles, each provided with three bloom cladding, they are grown - up bell- shaped urn. In many species, the inner and outer bracts are greatly different. There are one (only with Oxygyne ) or two circles with three stamens present; they are among themselves freely but intertwine with the bloom cladding; they are bent inwardly. In Haplothismia and Oxygyne the stamens are wider at the base; in the other genera the stamens are either reduced or specialized. The pollen grains have an aperture. Three carpels are a inferior ovary adherent to 50 to 100 anatrope ovules. The often short style ends in a three-lobed stigma.

Fruit and seeds

The thick-walled capsule fruit contains 50 to 150 seeds and opens at its tip. The tiny seeds have no endosperm and the embryo is only a rudimentary state in mature seeds.

Ingredients and chromosomes

It can be stored as Rhaphide calcium oxalate crystals.

The chromosomes are 1-4 microns long. The chromosomes amount to n = 6-9.

Systematics and distribution

The distribution Thismiaceae is holartisch, paläotropisch, neotropisch, australian and antarctic. Deposits are found mainly in Southeast Asia, Africa, America (especially Brazil ), Australia and New Zealand. The areas and the species are disjoint. They thrive mostly in tropical areas, but there are also some species in warm temperate zones, for example in Japan.

The first publication of the family name took place in 1858 by Jacob Georg Agardh in Theoria systematis Plantarum, 99 The type genus is Thismia handle ..

After molecular genetic studies, the taxa of the family are no longer incorporated into the tribe Thismieae within the family of Burmanniaceae, sister group of the family are the Taccaceae. The family consists of five genera with about 32 to 50 species:

  • Afrothismia ( Engl ) Schltr. With about nine species in the tropical rain forests of Africa.
  • Haplothismia Airy Shaw: With only one type: Haplothismia exannulata Airy Shaw in the Western Ghats in India.
  • Tiputinia foetida in the Amazon region of Ecuador.

Swell

  • Description of Thismiaceae in APWebsite. (Section Description and systematics)
  • The Thismiaceae at DELTA family. (English)
  • Vincent Merckx, Peter Schols, Hiltje Maas -van de Kamer, Paul Maas, Suzy Huysmans & Erik Smets: Phylogeny and evolution of Burmanniaceae ( Dioscoreales ) based on nuclear and mitochondrial data, in American Journal of Botany, 2006, 93, pp. 1684 -1698: Online.
  • Erik Vincent Merckx, Freek Bakker, Suzy Huysmans & Erik Smets: Bias and conflict in phylogenetic inference of myco - heterotrophic plants: a case study in Thismiaceae in Cladistics, Volume 25, Number 1, February 2009, pp. 64-77.
  • Vincent Merckx, Martin I. Bidartondo & Nicole A. Hynson: Myco - straight trophy: when fungi host plants, in Annals of Botany, 2009, ISSN: 1095-8290: PDF Online.
Mycotroph Perennial plant Ovary (botany) Vestigiality Holarctic Australasian ecozone Disjunct distribution Adolf Engler Tropical rainforest West Africa
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