[3] In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), it is the only genus in the family Hemidictyaceae.

[6] Hemidictyaceae is considered to be a sister family to Aspleniaceae s.l., believed to have diverged during the Cretaceous period.

[7][8] The following cladogram for the suborder Aspleniineae (as eupolypods II), based on Lehtonen (2011),[9] and Rothfels & al. (2012),[10] shows a likely phylogenetic relationship between the Hemidictyaceae and the other families of the clade.

Cystopteridaceae Rhachidosoraceae Diplaziopsidaceae Aspleniaceae Hemidictyaceae Thelypteridaceae Woodsiaceae Onocleaceae Blechnaceae Athyriaceae There is currently only one accepted Hemidictyum species, Hemidictyum marginatum.

[2] 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.