Cystopteridaceae, Eupolypods II, Polypodiales, Onocleaceae, Cystodium sorbifolium
Hemidictyaceae is a family of ferns in the order Polypodiales. Its sole genus is ''Hemidictyum'' , commonly known as the "marginated half net fern." Hemidictyaceae is considered to be a sister family to Aspleniaceae, believed to have diverged during the Cretaceous period.
The name Hemidictyum was derived from the terms hemi (half) and diktyon (net), from the veins being netted only half-way across the pinnules.
Hemidictyum is a native neotropical fern, found in Mexico, the Caribbean, Costa Rica, Guatemala, Honduras, Nicaragua, Panama, French Guiana, Suriname, Brazil, Venezuela, Puerto Rico, Bolivia, Colombia, Ecuador, and Peru.
There is currently only one accepted Hemidictyum species name, Hemidictyum marginatum. The other names are considered to be synonyms, either of that species, or of accepted Asplenium species:Hemidictyum marginatum (L.) C.Presl 1836
Hemidictyum purdieanum (Hook.) T.Moore 1857
Hemidictyum finlaysonianum (Wall. ex Hook) T.Moore 1857
The following diagram for the eupolypods II, based on Lehtonen, 2011, and Rothfels & al., 2012, shows a likely phylogenic relationship between the Hemidictyaceae and the other families of the eupolypods II clade.