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Welwitschia (Welwitschia mirabilis)

Welwitschia ( Welwitschia mirabilis )

without rank: Streptophyta
Empire : Plants (Plantae)
Department : Vascular plants (tracheophyta)
Subdivision : Seed plants (Spermatophytina)
Class : Coniferopsida
Order : Gnetales
Scientific name

The Gnetales are an order of the seed plants (Spermatophytina). They are naked animals (gymnosperms) and are currently part of the Coniferopsida due to their molecular genetic characteristics . The order includes 75 species in three genera.


In some characteristics the Gnetophyta resemble the Bedecktsamern (Magnoliophyta), but are probably not an ancestor of the same. The Gnetophyta have a woody sprout that runs underground in Welwitschia . The secondary wood contains vessels . The leaves are opposite or whorled.

The flowers are unisexual, so they have either only female or only male organs. They are grouped into inflorescences . The male flowers have a perianth (perianth). The seeds have two cotyledons .


Within the Gnetales there are three families , each with only one genus:

  • Sea shrub family (Ephedraceae Dum. )
    • Genus Meerträubel ( Ephedra Tourn. Ex L. ): 40 species of shrubs in arid regions of South America, the Sahara, the Mediterranean and Asia.
  • Family Gnetaceae Lindl.
  • Welwitschiagewächse family (Welwitschiaceae Caruel )
    • Genus Welwitschia Hook. f. : There is only one type.
      • Welwitschie ( Welwitschia mirabilis Hook. F. ): Namib desert of Namibia and Angola. It forms only two continuously growing, ribbon-shaped leaves and is up to 2000 years old. In 2001, two subspecies were described on the basis of six specimens cultivated in Berlin; this was often cited, but could not be confirmed in field studies. There are still no subspecies.


Individual evidence

  1. Nicholas Jacobson, Peter Jacobson, Ernst van Jaarsveld, Kathryn Jacobson: Field evidence from Namibia does not support the designation of Angolan and Namibian subspecies of Welwitschia mirabilis Hook. In: Transactions of the Royal Society of South Africa , Volume 69, Issue 3, 2014, pp. 179-186. doi : 10.1080 / 0035919X.2014.950187 .

Web links

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