Aspleniineae is a suborder of ferns in the order Polypodiales. It is equivalent to the clade eupolypods II in earlier systems; it is also treated as a single very broadly defined family Aspleniaceae. The suborder generally corresponds with the order Blechnales as described by J. L. Reveal in 1993. Aspleniineae includes some important ferns, including Onoclea sensibilis, the sensitive fern, which grows as a virtual weed throughout much of its temperate North American range, and ferns of the genus Thelypteris, a genus that has shown remarkable speciation. It also includes one of the more common horticultural ferns, Matteuccia struthiopteris, the ostrich fern.
In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), the group is treated as the suborder Aspleniinae, and divided into 11 families. Alternatively, it may be treated as a single, very broadly circumscribed family Aspleniaceae sensu lato, which is then divided into subfamilies. The relationship between the two approaches is shown in the table below.
| PPG I | Christenhusz & Chase (2014) | |
|---|---|---|
| Suborder Aspleniineae H.Schneid. & C.J.Rothf | Family Aspleniaceae Newman | |
| Family Cystopteridaceae Shmakov | Subfamily Cystopteridoideae Ching & Z.R.Wang | |
| Family Rhachidosoraceae X.C.Zhang | Subfamily Rhachidosoroideae M.L.Wang & Y.T.Hsieh | |
| Family Diplaziopsidaceae X.C.Zhang & Christenh. | Subfamily Diplaziopsidoideae Christenh. | |
| Family Desmophlebiaceae Mynssen | (The only genus was described after 2014.) | |
| Family Hemidictyaceae Christenh. & H.Schneid. | Subfamily Asplenioideae Link | |
| Family Aspleniaceae Newman | ||
| Family Woodsiaceae Herter | Subfamily Woodsioideae Schmakov | |
| Family Onocleaceae Pic.Serm. | Subfamily Blechnoideae Hook. | |
| Family Blechnaceae Newman | ||
| Family Athyriaceae Alston | Subfamily Athyrioideae B.K.Nayar | |
| Family Thelypteridaceae Ching ex Pic.Serm. | Subfamily Thelypteridoideae C.F.Reed |
The following diagram shows a likely phylogenic relationship between the families of Aspleniineae (as eupolypods II), based on Lehtonen (2011), and Rothfels & al. (2012).