What is "adiantaceae"

Adiantaceae (as construed here, sensu strictu, not a synonym of Pteridaceae) is a family of ferns in the order Pteridales. This includes the family formerly known as the "Vittariaceae." Recent genetic analyses based on chloroplast genes demonstrate that the vittarioid ferns cladistically nest within the genus Adiantum, making that genus paraphyletic.

left|thumb|Adiantum lunulatum in Goa, India

The vittarioid ferns are primarily epiphytic in tropical regions and all have simple leaves with sori that follow the veins and lack true indusia; the sori are most often marginal with a false indusium formed from the reflexed leaf margin. The family also includes a species, Vittaria appalachiana, that is highly unusual in that the sporophyte stage of the life cycle is absent. This species consists solely of photosynthetic gametophytes that reproduce asexually.

The ferns historically considered as Adiantum include both petrophilic and terrestrial plants. Most of the species in this genus do compose a clade within the family, but apparently Adiantum raddianum and possibly some related species constitute a clade that is sister to the vittarioids combined with the rest of the genus Adiantum.

This family is most closely allied with the Pellaeaceae within the Pteridales.

Based on phylogenetic research, Smith et al. (2006) included Adiantaceae as part of the family Pteridaceae and Christenhusz et al. (2011) listed its genera in Vittarioideae , one of five subfamilies of Pteridaceae.