Most gnetophytes can be found living in the deserts or mountains of Asia, Africa and South America. The division
contains only three genera, which are all different in structure and
adaptations. The genus Gnetum is composed of tropical climbing
plants. The genus Ephedra contains shrublike plants and is the only
genus that can be found in the U.S. The third genus,Welwitschia, is
found only in South Africa. It is a low lying desert dweller that can live
over a 100 years.Welwitschia
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