Dicksoniaceae

Dicksoniaceae
Calochlaena dubia
Scientific classification
Kingdom:Plantae
Division:Pteridophyta
Class:Polypodiopsida/Pteridopsida
(disputed)
Order:Cyatheales
Family:Dicksoniaceae
Bower, nom. cons.
Genera

Calochlaena
Dicksonia
Lophosoria
†Conantiopteris
†Coniopteris
†Erboracia
†Lophosoriorhachis
†Nishidicaulis
†Onychiopsis

The Dicksoniaceae is a family of tropical, subtropical and warm temperate ferns. Most of the 5-6 genera in the family are terrestrial ferns or have very short trunks compared to tree ferns of the family Cyatheaceae. However, some of the larger species can reach several metres in height. A number of others are epiphytes. They are found mostly in tropical regions in the Southern Hemisphere, as far south as southern New Zealand. Larger tree ferns in the genus Cibotium were formerly included in Dicksoniaceae, but are now segregated as the family Cibotiaceae.

Morphology

Species in the family are generally characterized by large pinnate fronds, 1–4 m long. The family includes several species of tree ferns, which grow a single trunk, notably the species in Dicksonia. All members of the family have long, tapering hairs composed of cells arranged end to end, unlike the scales characteristic of the Cyatheaceae.

Evolution

The ferns of family Dicksoniaceae are generally regarded as more primitive than those of the family Cyatheaceae, having originated in the early Jurassic period.{Citation needed}

Diversity

Only 3 extant genera are recognised in this monophyletic family:

References

  • Classification of Ferns and Allies
  • Large, M.F. and J.E. Braggins (2004). Tree Ferns. Timber Press. ISBN 0-88192-630-2
  • Smith, A.R., K.M. Pryer, E. Schuettpelz, P. Korall, H. Schneider & P.G. Wolf 2006. "A classification for extant ferns" (PDF). Archived from the original (PDF) on 2008-02-26.  (420 KiB) Taxon 55(3): 705-731.
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