The plant division Gnetophyta consists of only three genera of woody plants grouped in the gymnosperms. The living gnetophytes are a handful of survivors of a group that was diverse and dominant in the Tertiary, and fossilized pollen attributed to a close relative of one of them, Ephedra, has been identified in the Early Cretaceous. They now comprise some 70 species across the three relict genera Gnetum (family Gnetaceae), Welwitschia (family Welwitschiaceae), and Ephedra (family Ephedraceae).
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