The Aspleniaceae (spleenworts) are a family of ferns, included in the order Polypodiales. The composition and classification of the family have been subject to considerable changes. In particular, there is a narrow circumscription, Aspleniaceae s.s., in which the family contains only two genera, and a very broad one, Aspleniaceae s.l., in which the family includes 10 other families kept separate in the narrow circumscription, with the Aspleniaceae s.s. being reduced to the subfamily Asplenioideae. The family has a worldwide distribution, with many species in both temperate and tropical areas. Elongated unpaired sori are an important characteristic of most members of the family.
Osmunda is a genus of primarily temperate-zone ferns of family Osmundaceae. Five to ten species have been listed for this genus.
Equisetales is an order of subclass Equisetidae with only one living family, Equisetaceae, containing the genus Equisetum (horsetails).
The order Salviniales is an order of ferns in the class Polypodiopsida.
Gleicheniales is an order of ferns in the subclass Polypodiidae. The Gleicheniales have records potentially as early as the Carboniferous, but the oldest unambiguous records date to the Permian.
The Dryopteridaceae are a family of leptosporangiate ferns in the order Polypodiales. They are known colloquially as the wood ferns. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), the family is placed in the suborder Polypodiineae. Alternatively, it may be treated as the subfamily Dryopteridoideae of a very broadly defined family Polypodiaceae sensu lato.
Salviniaceae, is a family of heterosporous ferns in the order Salviniales. The Salviniaceae contain the two genera Azolla and Salvinia, with about 20 known species in total. The oldest records of the family date to the Late Cretaceous. Azolla was previously placed in its own family, Azollaceae, but research has shown Azolla and Salvinia to be sister genera with the likely phylogenic relationship shown in the following diagram.
Psilotaceae is a family of ferns consisting of two genera, Psilotum and Tmesipteris with about a dozen species. It is the only family in the order Psilotales.
Diplazium esculentum, the vegetable fern, is an edible fern found throughout Asia and Oceania. It is probably the most commonly consumed fern.
The Athyriaceae are a family of terrestrial ferns in the order Polypodiales. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), the family is placed in the suborder Aspleniineae, and includes two genera. Alternatively, it may be treated as the subfamily Athyrioideae of a very broadly defined family Aspleniaceae. The family has with a cosmopolitan distribution.
Eusporangiate ferns are vascular spore plants, whose sporangia arise from several epidermal cells and not from a single cell as in leptosporangiate ferns. Typically these ferns have reduced root systems and sporangia that produce large amounts of spores.
Woodwardia fimbriata, known by the common name giant chain fern, is a fern species in the family Blechnaceae, in the eupolypods II clade of the order Polypodiales, in the class Polypodiopsida. It is native to western North America from British Columbia through California, including the Sierra Nevada, into Baja California.
Thelypteris is a genus of ferns in the subfamily Thelypteridoideae, family Thelypteridaceae, order Polypodiales. Two radically different circumscriptions of the genus are in use as of January 2020. In the Pteridophyte Phylogeny Group classification of 2016, the genus is a very small one with about two species. In other approaches, the genus is the only one in the subfamily Thelypteridoideae, and so includes between 875 and 1083 species.
Saccolomataceae is a family of ferns in the order Polypodiales with about 19 species. It has been formerly treated as part of the Dennstaedtiaceae, however it has been classified as its own family according to Smith et al. (2006) The genus Saccoloma has been classified to include Orthiopteris, but the phylogeny of the group not yet fully understood. The family includes a dozen known species.
Diplazium is a genus of ferns that specifically includes the approximately 400 known species of twinsorus ferns. The Greek root is diplazein meaning double: the indusia in this genus lie on both sides of the vein. These ferns were earlier considered part of either the Athyriaceae, Dryopteridaceae, Aspleniaceae, or Polypodiaceae families or recognized as belonging to their own taxonomic family. The Pteridophyte Phylogeny Group classification of 2016 places the genus in the Athyriaceae. The taxonomy of the genus is difficult and poorly known, and by 2009 has never been the subject of a complete monographic study. Their distribution is pantropical, with a few species extending into temperate areas.
Homalosorus is a genus of fern with only one species, Homalosorus pycnocarpos. It may also be referred to by its older synonyms Athyrium pycnocarpon and Diplazium pycnocarpon. Commonly referred to as the narrow-leaved glade fern, narrow-leaved-spleenwort, or glade fern, it is endemic to eastern North America and typically grows in moist woodlands. Once classified in the family Athyriaceae due to its linear, often doubled sori, in the Pteridophyte Phylogeny Group classification of 2016, it is placed in the small family Diplaziopsidaceae, whose other three species are native to east Asia. Other sources place the genus in the subfamily Diplaziopsidoideae of a very broadly defined family Aspleniaceae, equivalent to the suborder Aspleniineae in PPG I.
The Dipteridaceae is a family of ferns in the order Gleicheniales of the class Polypodiopsida. They are commonly known as umbrella ferns and contain two genera, Cheiropleuria and Dipteris, with a total of nine species confined to Asia, New Guinea and northern Australia While currently a small family, they were much more abundant in the Mesozoic era, with the oldest fossils being known from the Middle Triassic of Italy, Australia and Argentina. Seven fossil genera are recognised, including Hausmannia, Clathropteris, Dictyophyllum, Thaumatopteris, Camptopteris, and Polyphacelus.
Matoniaceae is one of the three families of ferns in the Gleicheniales order of the Polypodiopsida class. Fossil records reveal that Matoniaceae ferns were abundant during the Mesozoic era, during which they lived on every continent, including Antarctica, with eight genera and 26 species, with the oldest known specimens being from the Middle Triassic of Antarctica. Today the family is much less abundant, and also less diverse, with only two extant genera and four species, which are limited to portions of southeastern Asia.
Rhachidosorus is a genus of ferns in the order Polypodiales. It is the only genus in the family Rhachidosoraceae in the Pteridophyte Phylogeny Group classification of 2016. Alternatively, the genus may be placed in the subfamily Rhachidosoroideae of a more broadly defined family Aspleniaceae, the family placement used in Plants of the World Online as of November 2019.
Lindsaeineae is a suborder of ferns (Polypodiopsida), order Polypodiales, created by the Pteridophyte Phylogeny Group (2016). It consists of two monogeneric families plus the larger Lindsaeaceae with seven genera, and the suborder contains about 237 species overall. It corresponds to Lindsaeaceae sensu Smith 2016.
