Lygodium
Lygodium japonicum
Scientific classification
Kingdom:	Plantae
Division:	Pteridophyta
Class:	Pteridopsida
Order:	Schizaeales
Family:	Lygodiaceae C.Presl
Genus:	Lygodium Sw.
Species
See text

Lygodium (climbing fern) is a genus of about 40 species of ferns, native to tropical regions across the world, with a few temperate species in eastern Asia and eastern North America. It is the sole genus in the family Lygodiaceae, though included in the family Schizaeaceae by some botanists.

They are unusual in that the rachis, or midrib, of the frond is thin, flexible, and long, the frond unrolling with indeterminate growth and the rachis twining around supports, so that each frond forms a distinct vine. The fronds may be from 3-12 m long, depending on the species.

Lygodium is now considered a very problematic invasive species in the southern U.S. Populations of Lygodium have increased more than 12-fold over the past decade--as can be seen on IFAS's SRFer Mapserver.

Selected species

• Lygodium articulatum – Tropical southeast Asia.
• Lygodium circinatum – Tropical Asia and Australasia.
• Lygodium conforme – China.
• Lygodium cubense – Cuba, Hispaniola.
• Lygodium digitatum – China.
• Lygodium flexuosum – Southern China south to northern Australasia.
• Lygodium japonicum – Japanese climbing fern. Eastern Asia south to northern Australia.
• Lygodium microphyllum – Old World tropics.
• Lygodium microstachyum – China.
• Lygodium palmatum – American climbing fern. Eastern United States (rare, confined to acid soils).
• Lygodium polystachyum – China.
• Lygodium reticulatum – Australia, Polynesia.
• Lygodium salicifolium – Southern China south to northern Australasia.
• Lygodium scandens – Southern China south to northern Australia.
• Lygodium subareolatum – China.
• Lygodium trifurcatum – Tropical southeast Asia south to northern Australasia.
• Lygodium volubile – Northern South America, Central America, Caribbean.
• Lygodium versteeghii – Tropical southeast Asia south to northern Australasia.
• Lygodium yunnanense – Southern China.

[edit] References

Wikimedia Commons has media related to: Lygodium

• Flora of North America: Lygodium
• "Lygodium Sw.". Australian Plant Name Index (APNI), IBIS database. Centre for Plant Biodiversity Research, Australian Government. http://www.anbg.gov.au/cgi-bin/apni?taxon_id=46269. 
• Flora of China: Lygodium species list