Schizaeales

Schizaeales
Lygodium japonicum
Scientific classification
Kingdom:	Plantae
Division:	Pteridophyta
Class:	Polypodiopsida /  Pteridopsida (disputed)
Order:	Schizaeales
Families
Schizaeaceae Anemiaceae Lygodiaceae

Schizaeales is an order of fern (class Pteridopsida). The ferns in this order were once all lumped into the family Schizaeaceae in the old order Filicales. However, although they are demonstrably related, these ferns differ markedly, and so three groups have now been elevated to family status:

• The family Schizaeaceae are generally small ferns with forking fronds and a distinctive, somewhat non-fern-like, appearance.
• The family Anemiaceae look very fern-like and are typically terrestrial or epipetric.
• The family Lygodiaceae, or Climbing Ferns, look very ferny but are highly distinctive in their growth habit: the rachis of the frond is long and flexible, with indeterminate growth, so that the fronds form climbing or trailing vines.

At one time some workers believed the water ferns (order Salviniales) to be allied to this order because of certain structural similarities, but modern cladistic studies have ruled out any special alliance.

Evolution

Schizaeales had a northern hemisphere concentration as late as the Mesozoic, but by the Quaternary, there was a clear shift to a southern hemisphere distribution

References

• C.Michael Hogan. 2010. Fern. Encyclopedia of Earth, National Council for Science and the Environment. topic ed. Saikat Basu