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Welwitschia is a monotypic genus of gymnosperm plant, comprising the very distinct Welwitschia mirabilis. It is the only genus of the family Welwitschiaceae, in the order Welwitschiales, in the division Gnetophyta. The plant is considered a living fossil (Lewington and Parker, 118). This is a desert plant which grows from a short, thick trunk, with only two leaves that continuously grow from their base, and a long, thick taproot. After germination, the cotyledons grow to 25-35 mm in length, and are followed shortly afterwards by the appearance of the two permanent leaves. These leaves are produced opposite that of the cotyledons, and continue to grow throughout the life of the plant, eventually growing to 2-4 m long and usually becoming split into several strap-shaped sections. After these appear, two cotyledonary buds appear; in these, the growing tip dies, causing elongation of the buds. Growth continues sideways, which forms the obconical growth of the stem. The species is dioecious, with separate male and female plants.

The age of the plants is difficult to assess, but it is believed that they are very long-lived, possibly living 1000 years or more. Some individuals may be more than 2000 years old. The plant is thought to absorb water through peculiar structures on its leaves, harvesting moisture from the dew that comes into the desert every night. Named after Dr. Friedrich Welwitsch, it is generally considered to be one of the oddest plants in existence. Although considered endangered due to its very slow growth and the fact that older plants are desired by collectors, a fair number of plants exist in the wild. The plants living in Angola are generally considered to be better protected than the plants in Namibia, owing to the relatively high concentration of landmines in Angola, which keep collectors away .

The species grows readily from seed, which may be purchased from specialty seed dealers. The seed must be kept moist for the first couple of weeks and exposed to as much heat and light as possible during this time. Seeds collected from the wild are often heavily contaminated with spores of Aspergillus niger, which causes them to rot shortly after they germinate. Seeds from the Kirstenbosch National Botanical Garden in Cape Town, South Africa, or other cultivated sources are much cleaner and less likely to rot.

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Conservation of Welwitschia mirabilis - Brief description of the plant and challenges of cultivation, with an old botanical plate illustrating the plant's morphology.

Welwitschia mirabilis - Description and Information provided by the Ecology and Evolutionary Biology Conservatory
Meta Description: [ EEB Greenhouse Accession Data for Welwitschia mirabilis, EEB Greenhouse Index Page ]

Welwitschia mirabilis - Description, images, and tour route.
Meta Description: [ African adventure tours and safaris in Namibia: Welwitschia Mirabilis ]

Welwitschia mirabilis - Description of this dioecious perennial plant of southwest Africa, often described as unlike any known plant on earth.
Meta Description: [ Descriptions of Welwitschiaceae and Welwitschia mirabilis (tumbo). ]

500 West of Brandberg - A picture profile of the Northern Namib, its flora and fauna including Welwitschia mirablilis and lichens.
Meta Description: [ Pictures of the Erongo and Kenene Regions of Namibia ]

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