After Earle, 2002- and Donoghue, 1996-1998
<==o Gnetales Luerss. 1879 |--o Ephedraceae Dumortier (Mormon Tea or Joint Fir family) | `-- Ephedra Linnaeus 1753 ()? [37] `--+--o Welwitschiaceae Markgraf. | `-- Welwitschia mirabilis Hooker 1863 (welwitchia) `--o Gnetaceae Lindley `-- Gnetum Linnaeus ()? [32]
Reference(s):
- Earle, C. J., 2002-: Gnetales.
–iNet: The Gymnosperm Database: http://www.conifers.org - Donoghue, M. J., 1996-1998: Gnetales.
–iNet: The Tree of Life - Parker, S. P. (ed.), 1982: Synopsis and classification of living organisms. Vols. 1 & 2
–McGrew-Hill Book Company