# Fern

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Class of vascular plants

This article is about a group of plants. For other uses, see [Fern (disambiguation)](/source/Fern_(disambiguation)) and [Ferns (disambiguation)](/source/Ferns_(disambiguation)).

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Ferns Temporal range: Middle Devonian[1] – Present PreꞒ Ꞓ O S D C P T J K Pg N Polypodiales Equisetales Marattiales Osmundales Hymenophyllales Gleicheniales Cyatheales Psilotales Scientific classification Kingdom: Plantae Clade: Embryophytes Clade: Tracheophytes Division: Polypodiophyta Class: Polypodiopsida Cronquist, Takht. & W.Zimm. Subclasses[2] †Stauropterididae †Zygopterididae Equisetidae Marattiidae Ophioglossidae Polypodiidae Synonyms Filicatae Kubitski 1990 Filices Filicophyta Endlicher 1836 Monilophyta Cantino & Donoghue 2007 Pteridopsida Ritgen 1828

**Ferns** (**Polypodiopsida** or **Polypodiophyta**) are a group of [vascular plants](/source/Vascular_plant) ([land plants](/source/Land_plant) with [vascular tissues](/source/Vascular_tissue) such as [xylem](/source/Xylem) and [phloem](/source/Phloem)) that [reproduce](/source/Plant_reproduction) via [spores](/source/Spore) and have neither [seeds](/source/Seed) nor [flowers](/source/Flower). They differ from [non-vascular plants](/source/Non-vascular_plant) ([mosses](/source/Moss), [hornworts](/source/Hornwort) and [liverworts](/source/Liverwort)) by having specialized [transport bundles](/source/Vascular_bundle) that conduct [water](/source/Water) and [nutrients](/source/Nutrient) from and to the [roots](/source/Root), as well as [life cycles](/source/Biological_life_cycle) in which the branched [sporophyte](/source/Sporophyte) is the dominant phase.[3][4]

Ferns have [leaves](/source/Leaf) called [megaphylls](/source/Megaphyll) that are more complex than the [microphylls](/source/Microphyll) of [clubmosses](/source/Clubmoss). Most ferns are [leptosporangiate ferns](/source/Leptosporangiate_fern) that produce coiled [fiddleheads](/source/Fiddlehead_fern) that uncoil and expand into [fronds](/source/Frond). The group includes about 10,560 known extant species. Ferns are defined here in the broad sense, being all of the [Polypodiopsida](/source/Polypodiopsida), comprising both the leptosporangiate ([Polypodiidae](/source/Polypodiidae_(plant))) and [eusporangiate ferns](/source/Eusporangiate_fern), the latter group including [horsetails](/source/Horsetail), [whisk ferns](/source/Psilotaceae), [marattioid ferns](/source/Marattioid_fern) and [ophioglossoid ferns](/source/Ophioglossoid_fern).

The fern [crown group](/source/Crown_group), consisting of the leptosporangiates and eusporangiates, is estimated to have originated in the late [Silurian](/source/Silurian) period 423.2 million years ago during the [rapid radiation of land plants](/source/Silurian-Devonian_Terrestrial_Revolution),[5] but [Polypodiales](/source/Polypodiales), the group that makes up 80% of living fern diversity, did not appear and diversify until the [Cretaceous](/source/Cretaceous), contemporaneous with the [rise of](/source/Cretaceous_Terrestrial_Revolution) [flowering plants](/source/Flowering_plant) that came to dominate the world's flora.

Ferns are not of major economic importance, but some are used for [food](/source/Food), [medicine](/source/Medicinal_plants), as [biofertilizer](/source/Biofertilizer), as [ornamental plants](/source/Ornamental_plant), and for remediating contaminated soil. They have been the subject of research for their ability to remove some chemical pollutants from the atmosphere. Some fern species, such as bracken (*[Pteridium aquilinum](/source/Pteridium_aquilinum)*) and water fern (*[Azolla filiculoides](/source/Azolla_filiculoides)*), are significant [weeds](/source/Weed) worldwide. Some fern genera, such as *[Azolla](/source/Azolla)*, can [fix nitrogen](/source/Nitrogen_fixation) and make a significant input to the nitrogen nutrition of [rice paddies](/source/Paddy_field). They also play certain roles in folklore.

## Description

### Sporophyte

Homegrown fern in Brazil

Extant ferns are herbaceous [perennials](/source/Perennial_plant) and most lack [woody](/source/Wood) growth.[6] When woody growth is present, it is found in the stem.[7] Their foliage may be [deciduous](/source/Deciduous) or [evergreen](/source/Evergreen),[8] and some are semi-evergreen depending on the climate.[9] Like the sporophytes of seed plants, those of ferns consist of stems, leaves and roots. Ferns differ from [spermatophytes](/source/Spermatophyte) in that they reproduce by spores rather than by seeds.[7] However, they also differ from spore-producing [bryophytes](/source/Bryophyte) in that, like seed plants, they are [polysporangiophytes](/source/Polysporangiophyte), their [sporophytes](/source/Sporophyte) branching and producing many sporangia. Unlike those of bryophytes, fern sporophytes are free-living and only briefly dependent on the maternal [gametophyte](/source/Gametophyte).

The [green](/source/Green), [photosynthetic](/source/Photosynthesis) part of the plant is technically a [megaphyll](/source/Microphyll#evolution_of_leaves:_microphyll_and_megaphyll) and in ferns, it is often called a *[frond](/source/Frond)*. In [leptosporangiate ferns](/source/Leptosporangiate_fern) new leaves typically expand by the unrolling of a tight spiral called a crozier or [fiddlehead](/source/Fiddlehead_fern) into fronds.[10] This uncurling of the leaf is termed [circinate vernation](/source/Circinate_vernation). In some families, such as the [Blechnaceae](/source/Blechnaceae), the leaves are divided into two types, [sporophylls](/source/Sporophyll) or fertile fronds that produce spores and [trophophylls](https://en.wikipedia.org/w/index.php?title=Trophophyll&action=edit&redlink=1) or sterile fronds that do not.[11]: 32 Fern spores are borne in [sporangia](/source/Sporangia) which are usually clustered to form [sori](/source/Sorus). The sporangia may be covered with a protective coating called an [indusium](/source/Indusium). The arrangement of the [sporangia](/source/Sporangium) is important in classification.[7]

In monomorphic ferns, the fertile and sterile leaves look morphologically the same, and both are able to [photosynthesize](/source/Photosynthesis). In hemidimorphic ferns, just a portion of the fertile leaf is different from the sterile leaves. In dimorphic (holomorphic) ferns, the two types of leaves are [morphologically distinct](/source/Frond_dimorphism).[12] The fertile leaves are much narrower than the sterile leaves, and may have no green tissue at all, as in the [Blechnaceae](/source/Blechnaceae) and [Lomariopsidaceae](/source/Lomariopsidaceae).

Croziers, fronds, and [rhizomes](/source/Rhizome) of bracken. In this species the stems grow underground, allowing the plant to spread horizontally.

The anatomy of fern leaves can be anywhere from simple to highly divided, or even [indeterminate](/source/Indeterminate_growth) (e.g. [Gleicheniaceae](/source/Gleicheniaceae), [Lygodiaceae](/source/Lygodium)). The divided forms are [pinnate](/source/Pinnation), where the leaf segments are completely separated from one other, or pinnatifid (partially pinnate), where the leaf segments are still partially connected. When the fronds are branched more than once, it can also be a combination of the pinnatifid are pinnate shapes. If the leaf blades are divided twice, the plant has bipinnate fronds, and tripinnate fronds if they branch three times, and all the way to tetra- and pentapinnate fronds.[13][14] In tree ferns, the main stalk that connects the leaf to the stem (known as the stipe), often has multiple leaflets. The leafy structures that grow from the stipe are known as pinnae and are often again divided into smaller pinnules.[15]

Fern stems are often loosely called [rhizomes](/source/Rhizome), even though they grow underground only in some of the species. Epiphytic species and many of the terrestrial ones have above-ground creeping [stolons](/source/Stolon) (e.g., [Polypodiaceae](/source/Polypodiaceae)), and many groups have above-ground erect semi-woody trunks (e.g., [Cyatheaceae](/source/Cyatheaceae), the scaly tree ferns). These can reach up to 20 meters (66 ft) tall in a few species (e.g., *[Cyathea brownii](/source/Cyathea_brownii)* on [Norfolk Island](/source/Norfolk_Island) and *[Cyathea medullaris](/source/Cyathea_medullaris)* in [New Zealand](/source/New_Zealand)).[16]

[Roots](/source/Root) are underground non-photosynthetic structures that take up water and nutrients from [soil](/source/Soil). They are always [fibrous](/source/Fibrous_root_system) and are structurally very similar to the roots of seed plants.[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*]

### Gametophyte

As in all [vascular plants](/source/Vascular_plant), the [sporophyte](/source/Sporophyte) is the dominant phase or [generation in the life cycle](/source/Alternation_of_generations). The [gametophytes](/source/Gametophyte) of ferns, however, are very different from those of seed plants. They are free-living and resemble [liverworts](/source/Liverworts), whereas those of seed plants develop within the spore wall and are dependent on the parent sporophyte for their nutrition.[17] A fern gametophyte typically consists of:[3]

- [Prothallus](/source/Prothallus): A green, photosynthetic structure, whose initial growth is planar in one cell layer,[18] usually heart or kidney shaped, 3–10 mm long and 2–8 mm broad.[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*] The prothallus produces gametes by means of: - [Antheridia](/source/Antheridium): Small spherical structures that produce [flagellate](/source/Flagellum) antherozoids.[19] - [Archegonia](/source/Archegonium): A flask-shaped structure that produces a single egg at the bottom, reached by the male gametophyte by swimming down the neck.[3]

- [Rhizoids](/source/Rhizoid): [root](/source/Root)-like structures (not true roots) that consist of single[20] greatly elongated cells, that absorb water and mineral [salts](/source/Salts) over the whole structure. Rhizoids anchor the prothallus to the soil.[3]

## Life cycle and reproduction

New fern (*[Onoclea sensibilis](/source/Onoclea_sensibilis)*) emerges from the [prothallus](/source/Prothallus).

The lifecycle of a fern involves two stages, as in [club mosses](/source/Lycopodiopsida) and [horsetails](/source/Equisetum). In stage one, the spores are produced by [sporophytes](/source/Sporophyte) in [sporangia](/source/Sporangium), which are clustered together in sori (s.g. *sorus*), developing on the underside of fertile fronds. In stage two, the spores germinate into short-lived gamete-producing structures called [gametophytes](/source/Gametophyte) anchored to the ground by [rhizoids](/source/Rhizoid). When a mature fertile frond bears sori, and spores are released, the spores will settle on the soil and germinate to form initial rhizoids and protonemata that develop into the gametophyte's [prothallus](/source/Prothallus).[21] The prothallus bears spherical [antheridia](/source/Antheridium) (s.g. *antheridium*) which produce antherozoids (male gametophytes) and [archegonia](/source/Archegonium) (s.g. *archegonium*) which release a single [oosphere](/source/Egg_cell). The antherozoid swims up the archegonium and fertilizes the oosphere, resulting in a zygote, which will grow into a separate sporophyte, while the gametophyte shortly persists as a free-living plant.[3][22]

Ferns are [vascular plants](/source/Vascular_plant) differing from [lycophytes](/source/Lycophyte) by having true [leaves](/source/Leaf) (megaphylls), which are often [pinnate](/source/Pinnate).[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*] They differ from [seed plants](/source/Spermatophyte) ([gymnosperms](/source/Gymnosperm) and [angiosperms](/source/Angiosperm)) in reproducing by means of spores and lacking [flowers](/source/Flower) and [seeds](/source/Seed). Like all [land plants](/source/Embryophyte), they have a [life cycle](/source/Biological_life_cycle) referred to as [alternation of generations](/source/Alternation_of_generations), characterized by alternating [diploid](/source/Diploid) [sporophytic](/source/Sporophyte) and [haploid](/source/Haploid) [gametophytic](/source/Gametophyte) phases. The diploid sporophyte has 2*n* paired [chromosomes](/source/Chromosome), where *n* varies from species to species. The haploid gametophyte has *n* unpaired chromosomes, i.e. half the number of the sporophyte. The gametophyte of ferns is a free-living organism, whereas the gametophyte of the gymnosperms and angiosperms is dependent on the sporophyte.[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*]

The life cycle of a typical fern proceeds as follows:

1. A diploid sporophyte phase produces haploid [spores](/source/Spore) by [meiosis](/source/Meiosis) (a process of cell division which reduces the number of chromosomes by a half).

1. A spore grows into a free-living haploid gametophyte by [mitosis](/source/Mitosis) (a process of cell division which maintains the number of chromosomes). The gametophyte typically consists of a photosynthetic [prothallus](/source/Prothallus).

1. The gametophyte produces [gametes](/source/Gametes) (often both [sperm](/source/Sperm) and [eggs](/source/Ovum) on the same prothallus) by mitosis.

1. A mobile, [flagellate](/source/Flagellum) sperm fertilizes an egg that remains attached to the prothallus.

1. The fertilized egg is now a diploid [zygote](/source/Zygote) and grows by mitosis into a diploid sporophyte (the typical fern plant).

Sometimes a gametophyte can give rise to sporophyte traits like roots or sporangia without the rest of the sporophyte.[23]

[Sori](/source/Sorus) of [monarch fern](/source/Monarch_fern) contain clusters of [sporangia](/source/Sporangia)

## Taxonomy

[Carl Linnaeus](/source/Carl_Linnaeus) (1753) originally recognized 15 genera of ferns and fern allies, classifying them in class [Cryptogamia](/source/Cryptogamia) in two groups, Filices (e.g. *[Polypodium](/source/Polypodium)*) and [Musci](/source/Musci) (mosses).[24][25][26] By 1806 this had increased to 38 genera,[27] and has progressively increased since (*see [Schuettpelz et al (2018)](#CITEREFSchuettpelz_et_al2018)*). Ferns were traditionally classified in the [class](/source/Class_(biology)) Filices, and later in a [Division](/source/Phylum) of the Plant Kingdom named [Pteridophyta](/source/Pteridophyta) or Filicophyta. Pteridophyta is no longer recognised as a valid [taxon](/source/Taxon) because it is [paraphyletic](/source/Paraphyletic). The ferns are also referred to as Polypodiophyta or, when treated as a subdivision of [Tracheophyta](/source/Tracheophyta) (vascular plants), Polypodiopsida, although this name sometimes only refers to leptosporangiate ferns. Traditionally, all of the spore producing [vascular plants](/source/Vascular_plant) were informally denominated the [pteridophytes](/source/Pteridophyte), rendering the term synonymous with ferns and [fern allies](/source/Fern_allies). This can be confusing because members of the division Pteridophyta were also denominated pteridophytes (*sensu stricto*).[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*]

Traditionally, three discrete groups have been denominated ferns: two groups of eusporangiate ferns, the families [Ophioglossaceae](/source/Ophioglossaceae) ([adder's tongues](/source/Ophioglossum), [moonworts](/source/Moonwort), and grape ferns) and [Marattiaceae](/source/Marattiaceae); and the leptosporangiate ferns. The Marattiaceae are a primitive group of tropical ferns with large, fleshy rhizomes and are now thought to be a [sibling taxon](/source/Sister_group) to the leptosporangiate ferns. Several other groups of species were considered fern allies: the [clubmosses](/source/Clubmoss), [spikemosses](/source/Spikemoss), and [quillworts](/source/Iso%C3%ABtes) in [Lycopodiophyta](/source/Lycopodiophyta); the whisk ferns of [Psilotaceae](/source/Psilotaceae); and the horsetails of [Equisetaceae](/source/Equisetaceae). Since this grouping is [polyphyletic](/source/Polyphyly), the term fern allies should be abandoned, except in a historical context.[28] More recent genetic studies demonstrated that the Lycopodiophyta are more distantly related to other [vascular plants](/source/Vascular_plant), having radiated evolutionarily at the base of the vascular plant [clade](/source/Clade), while both the whisk ferns and horsetails are as closely related to leptosporangiate ferns as the [ophioglossoid ferns](/source/Ophioglossoid_fern) and Marattiaceae. In fact, the whisk ferns and ophioglossoid ferns are demonstrably a clade, and the [horsetails](/source/Horsetail) and Marattiaceae are arguably another clade.[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*]

### Molecular phylogenetics

Smith et al. (2006) carried out the first higher-level pteridophyte classification published in the [molecular phylogenetic](/source/Molecular_phylogenetic) era, and considered the ferns as monilophytes, as follows:[29]

- [Division](/source/Division_(botany)) [Tracheophyta](/source/Tracheophyta) (tracheophytes) – vascular plants - [Sub division](/source/Subdivision_(botany)) [Euphyllophytina](/source/Euphyllophytina) (euphyllophytes) - Infradivision [Moniliformopses](/source/Moniliformopses) (**monilophytes**) - Infradivision [Spermatophyta](/source/Spermatophyta) – seed plants, ~260,000 species - Subdivision [Lycopodiophyta](/source/Lycopodiophyta) (lycophytes) – less than 1% of extant vascular plants

Molecular data, which remain poorly constrained for many parts of the plants' phylogeny, have been supplemented by morphological observations supporting the inclusion of Equisetaceae in the ferns, notably relating to the construction of their sperm and peculiarities of their roots.[29]

The leptosporangiate ferns are sometimes called "true ferns".[30] This group includes most plants familiarly known as ferns. Modern research supports older ideas based on morphology that the Osmundaceae diverged early in the evolutionary history of the leptosporangiate ferns; in certain ways this family is intermediate between the eusporangiate ferns and the leptosporangiate ferns. Rai and Graham (2010) broadly supported the primary groups, but queried their relationships, concluding that "at present perhaps the best that can be said about all relationships among the major lineages of monilophytes in current studies is that we do not understand them very well".[31] Grewe et al. (2013) confirmed the inclusion of horsetails within ferns *sensu lato*, but also suggested that uncertainties remained in their precise placement.[32] Other classifications have raised Ophioglossales to the rank of a fifth class, separating the whisk ferns and ophioglossoid ferns.[32]

### Phylogeny

The ferns are related to other groups as shown in the following cladogram:[28][33][34][2]

Tracheophyta Lycophytes Euphyllophyta Ferns Spermatophyta Gymnosperms Angiosperms (seed plants) (vascular plants)

### Nomenclature and subdivision

Further information: [List of fern families](/source/List_of_fern_families)

The classification of Smith et al. in 2006 treated ferns as four classes:[29][35]

- [Equisetopsida](/source/Equisetidae) (Sphenopsida) – 1 order, [Equisetales](/source/Equisetales) ([Horsetails](/source/Horsetail)) ~ 15 species

- [Psilotopsida](/source/Ophioglossidae) – 2 orders ([whisk ferns](/source/Psilotaceae) and [ophioglossoid ferns](/source/Ophioglossoid_fern)) ~92 species

- [Marattiopsida](/source/Marattiidae) – 1 order, [Marattiales](/source/Marattiales) ~ 150 species

- [Polypodiopsida](/source/Polypodiidae_(plant)) (Filicopsida) – 7 orders ([leptosporangiate ferns](/source/Leptosporangiate_fern)) ~ 9,000 species

In addition they defined 11 orders and 37 families.[29] That system was a consensus of a number of studies, and was further refined.[32][36] The phylogenetic relationships are shown in the following [cladogram](/source/Cladogram) (to the level of orders).[29][37][32] This division into four major clades was then confirmed using [morphology](/source/Plant_morphology) alone.[38]

Tracheophyta Lycopodiophytes (club mosses, spike mosses, quillworts) Euphyllophytes Spermatophytes (seed plants) Ferns Equisetopsida Equisetales (horsetails) Psilotopsida Ophioglossales (grapeferns etc.) Psilotales (whisk ferns) Marattiopsida Marattiales Polypodiopsida Osmundales Hymenophyllales (filmy ferns) Gleicheniales Schizaeales Salviniales (heterosporous) Cyatheales (tree ferns) Polypodiales Eusporangiate Ferns Leptosporangiate Ferns

Subsequently, [Chase](/source/Mark_W._Chase) and [Reveal](/source/James_L._Reveal) considered both lycopods and ferns as subclasses of a class Equisetopsida ([Embryophyta](/source/Embryophyta)) encompassing all land plants. This is referred to as [Equisetopsida](/source/Equisetopsida_sensu_lato) *[sensu lato](/source/Sensu_lato)* to distinguish it from the narrower use to refer to horsetails alone, [Equisetopsida](/source/Equisetopsida) *sensu stricto*. They placed the lycopods into subclass Lycopodiidae and the ferns, keeping the term monilophytes, into five subclasses, Equisetidae, Ophioglossidae, Psilotidae, Marattiidae and Polypodiidae, by dividing Smith's Psilotopsida into its two orders and elevating them to subclass (Ophioglossidae and Psilotidae).[34] Christenhusz et al.[a] (2011) followed this use of subclasses but recombined Smith's Psilotopsida as Ophioglossidae, giving four subclasses of ferns again.[39]

[Christenhusz](/source/Christenhusz) and [Chase](/source/Mark_Chase) (2014) developed a new classification of ferns and lycopods. They used the term Polypodiophyta for the ferns, subdivided like Smith et al. into four groups (shown with equivalents in the Smith system), with 21 families, approximately 212 genera and 10,535 species;[28]

- [Equisetidae](/source/Equisetidae) (=Equisetopsida) – [monotypic](/source/Monotypic) (Equisetales, [Equisetaceae](/source/Equisetaceae), *[Equisetum](/source/Equisetum)*) horsetails ~ 20 species)

- [Ophioglossidae](/source/Ophioglossidae) (=Psilotopsida) – 2 monotypic orders ~ 92 species

- [Marattiidae](/source/Marattiidae) (=Marattiopsida) – 1 monotypic order (Marattiales, [Marattiaceae](/source/Marattiaceae), 2 subfamilies) ~ 130 species

- [Polypodiidae](/source/Polypodiidae_(plant)) (=Polypodiopsida) – 7 orders

This was a considerable reduction in the number of families from the 37 in the system of Smith et al., since the approach was more that of [lumping](/source/Lumping) rather than splitting. For instance a number of families were reduced to subfamilies. Subsequently, a [consensus](/source/Scientific_consensus) group was formed, the [Pteridophyte Phylogeny Group](/source/Pteridophyte_Phylogeny_Group) (PPG), analogous to the [Angiosperm Phylogeny Group](/source/Angiosperm_Phylogeny_Group), publishing their first complete classification in November 2016. They recognize ferns as a class, the Polypodiopsida, with four subclasses as described by Christenhusz and Chase, and which are phylogenetically related as in this cladogram:

Christenhusz and Chase 2014[2] Nitta et al. 2022[5] and Fern Tree of life[40] Polypodiopsida Equisetidae Equisetales Ophioglossidae Ophioglossales Psilotales Marattiidae Marattiales Polypodiidae Osmundales Hymenophyllales Gleicheniales Schizaeales Salviniales Cyatheales Polypodiales Equisetidae Equisetales Ophioglossidae Psilotales Ophioglossales Marattiidae Marattiales Polypodiidae Osmundales Hymenophyllales Gleicheniales Dipteridales Schizaeales Salviniales Cyatheales Polypodiales

In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), the Polypodiopsida consist of four subclasses, 11 orders, 48 families, 319 genera, and an estimated 10,578 species.[41] Thus Polypodiopsida in the broad sense (*sensu lato*) as used by the PPG (Polypodiopsida *sensu* PPG I) needs to be distinguished from the narrower usage (*sensu stricto*) of Smith et al. (Polypodiopsida *sensu* Smith et al.)[2] Classification of ferns remains unresolved and controversial with competing viewpoints ([splitting vs lumping](/source/Splitting_vs_lumping)) between the systems of the PPG on the one hand and Christenhusz and Chase on the other, respectively. In 2018, Christenhusz and Chase explicitly argued against recognizing as many genera as PPG I.[26][42]

Comparison of fern subdivisions in some classifications Smith et al. (2006)[29] Chase & Reveal (2009)[34] Christenhusz et al. (2011)[39] Christenhusz & Chase (2014, 2018)[28][43] PPG I (2016)[2] ferns (no rank) monilophytes (no rank) ferns (monilophytes) (no rank) ferns (Polypodiophyta) (no rank) Class Polypodiopsida Class Equisetopsida Subclass Equisetidae Subclass Equisetidae Subclass Equisetidae Subclass Equisetidae Class Psilotopsida Subclass Ophioglossidae Subclass Psilotidae Subclass Ophioglossidae Subclass Ophioglossidae Subclass Ophioglossidae Class Marattiopsida Subclass Marattiidae Subclass Marattiidae Subclass Marattiidae Subclass Marattiidae Class Polypodiopsida Subclass Polypodiidae Subclass Polypodiidae Subclass Polypodiidae Subclass Polypodiidae

### Evolution and biogeography

Fern-like taxa (*[Wattieza](/source/Wattieza)*) first appear in the fossil record in the middle [Devonian](/source/Devonian) period, ca. 390 [Mya](/source/Mya_(unit)). By the [Triassic](/source/Triassic), the first evidence of ferns related to several modern families appeared. The great fern radiation occurred in the late [Cretaceous](/source/Cretaceous), when many modern families of ferns first appeared.[44][1][45][46] Ferns evolved to cope with low-light conditions present under the canopy of angiosperms.

Remarkably, the [photoreceptor](/source/Photoreceptor_protein) neochrome in the two orders Cyatheales and Polypodiales, integral to their adaptation to low-light conditions, was obtained via [horizontal gene transfer](/source/Horizontal_gene_transfer) from [hornworts](/source/Hornwort), a [bryophyte](/source/Bryophyte) lineage.[47]

Due to the very large genome seen in most ferns, it was suspected they might have gone through [whole genome duplications](/source/Paleopolyploidy), but [DNA sequencing](/source/DNA_sequencing) has shown that their genome size is caused by the accumulation of mobile DNA like [transposons](/source/Transposable_element) and other genetic elements that infect genomes and get copied over and over again.[48]

Ferns appear to have evolved [extrafloral nectaries](/source/Extrafloral_nectaries) 135 million years ago, nearly simultaneously with the trait's evolution in angiosperms. However, nectary-associated diversifications in ferns did not hit their stride until nearly 100 million years later, in the [Cenozoic](/source/Cenozoic). There is weak support for the rise of fern-feeding arthropods driving this diversification.[49]

## Distribution and habitat

Ferns are widespread in their distribution, with the greatest richness in the tropics and least in arctic areas. The greatest diversity occurs in tropical rainforests.[50] New Zealand, for which the fern is a symbol, has about 230 species, distributed throughout the country.[51] It is a common plant in [European](/source/Europe) forests.

## Ecology

Fern species live in a wide variety of [habitats](/source/Habitat), from remote [mountain](/source/Mountain) elevations, to dry [desert](/source/Desert) rock faces, bodies of water or open fields. Ferns in general may be thought of as largely being specialists in marginal habitats, often succeeding in places where various environmental factors limit the success of [flowering plants](/source/Flowering_plant). Some ferns are among the world's most serious [weed](/source/Weed) species, including the [bracken](/source/Bracken) fern growing in the Scottish highlands, or the mosquito fern (*[Azolla](/source/Azolla)*) growing in tropical lakes, both species forming large aggressively spreading colonies. There are four particular types of habitats that ferns are found in: moist, shady [forests](/source/Forest); crevices in rock faces, especially when sheltered from the full sun; acid wetlands including [bogs](/source/Bog) and [swamps](/source/Swamp); and tropical [trees](/source/Tree), where many species are [epiphytes](/source/Epiphyte) (something like a quarter to a third of all fern species).[52]

The epiphytic ferns in particular have turned out to be hosts of a huge diversity of invertebrates. It is assumed that [bird's-nest ferns](/source/Bird's-nest_fern) alone contain up to half the invertebrate biomass within a hectare of [rainforest](/source/Rainforest) canopy.[53]

Many ferns depend on associations with [mycorrhizal](/source/Mycorrhizal) fungi. Many ferns grow only within specific pH ranges; for instance, the climbing fern (*[Lygodium palmatum](/source/Lygodium_palmatum)*) of eastern [North America](/source/North_America) will grow only in moist, intensely [acid](/source/Acid) soils, while the bulblet bladder fern (*[Cystopteris bulbifera](/source/Cystopteris_bulbifera)*), with an overlapping range, is usually found on [limestone](/source/Limestone).[54]

The spores are rich in [lipids](/source/Lipid), [protein](/source/Protein) and [calories](/source/Calories), so some vertebrates eat these. The [European woodmouse](/source/European_woodmouse) (*Apodemus sylvaticus*) has been found to eat the spores of *[Culcita macrocarpa](/source/Culcita_macrocarpa)*, and the [bullfinch](/source/Bullfinch) (*Pyrrhula murina*) and the [New Zealand lesser short-tailed bat](/source/New_Zealand_lesser_short-tailed_bat) (*Mystacina tuberculata*) also eat fern spores.[55]

		- In undergrowth below [coast redwoods](/source/Sequoia_sempervirens), California

		- Fern bed under a forest canopy, Virginia

		- On a wall

		- hart's tongue fern *[Asplenium scolopendrium](/source/Asplenium_scolopendrium)* in a [gryke](https://en.wiktionary.org/wiki/gryke) in [limestone pavement](/source/Limestone_pavement)

		- [Epiphytic](/source/Epiphyte) ferns in India

		- *[Azolla](/source/Azolla)* duckweed fern covering the [Canning River](/source/Canning_River), Western Australia

## Uses

Ferns are not as important economically as seed plants, but have considerable importance in some societies. Some ferns are used for food, including the fiddleheads of *Pteridium aquilinum* ([bracken](/source/Bracken)), *Matteuccia struthiopteris* ([ostrich fern](/source/Ostrich_fern)), and *Osmundastrum cinnamomeum* ([cinnamon fern](/source/Cinnamon_fern)). *[Diplazium esculentum](/source/Diplazium_esculentum)* is also used in the tropics (for example in *budu pakis*, a traditional dish of [Brunei](/source/Brunei))[56] as food. Tubers from the "para", *[Ptisana salicina](/source/Ptisana_salicina)* (king fern) are a traditional food in [New Zealand](/source/New_Zealand) and the [South Pacific](/source/Oceania). Fern tubers were used for food 30,000 years ago in Europe.[57][58] Fern tubers were used by the [Guanches](/source/Guanches) to make [gofio](/source/Gofio) in the [Canary Islands](/source/Canary_Islands). Ferns are generally not known to be poisonous to humans.[59] [Licorice fern](/source/Licorice_fern) [rhizomes](/source/Rhizome) were chewed by the natives of the [Pacific Northwest](/source/Pacific_Northwest) for their flavor.[60] Some species of ferns are [carcinogenic](/source/Carcinogenic), and the British Royal Horticultural Society has advised not to consume any species for health reasons of both humans and livestock.[61]

Ferns of the genus *Azolla*, commonly known as water fern or mosquito ferns are very small, floating plants that do not resemble ferns. The mosquito ferns are used as a biological fertilizer in the rice paddies of southeast Asia, taking advantage of their ability to [fix nitrogen](/source/Nitrogen_fixation) from the air into compounds that can then be used by other plants.

Ferns have proved resistant to phytophagous insects. The gene that express the protein Tma12 in an edible fern, *[Tectaria macrodonta](https://en.wikipedia.org/w/index.php?title=Tectaria_macrodonta&action=edit&redlink=1)*, has been transferred to cotton plants, which became resistant to [whitefly](/source/Whitefly) infestations.[62]

Many ferns are grown in [horticulture](/source/Horticulture) as landscape plants, for [cut foliage](/source/Foliage) and as [houseplants](/source/Houseplant), especially the Boston fern (*[Nephrolepis exaltata](/source/Nephrolepis_exaltata)*) and other members of the genus *[Nephrolepis](/source/Nephrolepis)*. The [bird's nest fern](/source/Asplenium_nidus) (*Asplenium nidus*) is also popular, as are the [staghorn ferns](/source/Staghorn_fern) (genus *Platycerium*). Perennial (also known as hardy) ferns planted in gardens in the northern hemisphere also have a considerable following.[63]

Several ferns, such as bracken[64] and *Azolla*[65] species are noxious [weeds](/source/Weed) or [invasive species](/source/Invasive_species). Further examples include Japanese climbing fern (*[Lygodium japonicum](/source/Lygodium_japonicum)*), [sensitive fern](/source/Sensitive_fern) (*Onoclea sensibilis*) and Giant water fern (*[Salvinia molesta](/source/Salvinia_molesta)*), one of the world's worst aquatic weeds.[66][67] The important fossil fuel [coal](/source/Coal) consists of the remains of primitive plants, including ferns.[68]

## Culture

Ferns in the [Victorian era](/source/Victorian_era): *Blätter des Manns Walfarn* by [Alois Auer](/source/Alois_Auer), Vienna: Imperial Printing Office, 1853

### Pteridology

The study of ferns and other pteridophytes is called **pteridology**. A **pteridologist** is a specialist in the study of pteridophytes in a broader sense that includes the more distantly related [lycophytes](/source/Lycophyte).

### Pteridomania

[Pteridomania](/source/Pteridomania) was a [Victorian era](/source/Victorian_era) [craze](/source/Fads_and_trends) which involved fern [collecting](/source/Collecting) and fern motifs in [decorative art](/source/Decorative_art) including [pottery](/source/Pottery), [glass](/source/Glass), [metals](/source/Metal), [textiles](/source/Textile), [wood](/source/Wood), [printed paper](/source/Printing), and [sculpture](/source/Sculpture) "appearing on everything from [christening](/source/Infant_baptism) presents to [gravestones](/source/Gravestone) and memorials." The fashion for growing ferns indoors led to the development of the [Wardian case](/source/Wardian_case), a glazed cabinet that would exclude air pollutants and maintain the necessary humidity.[69][70]

### Other applications

[Barnsley fern](/source/Barnsley_fern) created using a [chaos game](/source/Chaos_game), through an [Iterated function system](/source/Iterated_function_system)[71]

The **Barnsley fern** is a [fractal](/source/Fractal) named after the British [mathematician](/source/Mathematician) [Michael Barnsley](/source/Michael_Barnsley) who first described it in his book *Fractals Everywhere*. A [self-similar](/source/Self-similarity) structure is described by a mathematical function, applied repeatedly at different scales to create a frond pattern.[71]

The dried form of ferns was used in other arts, such as a stencil or directly inked for use in a design. The botanical work, *[The Ferns of Great Britain and Ireland](/source/The_Ferns_of_Great_Britain_and_Ireland)*, is a notable example of this type of [nature printing](/source/Nature_printing). The process, patented by the artist and publisher Henry Bradbury, impressed a specimen on to a soft lead plate. The first publication to demonstrate this was [Alois Auer](/source/Alois_Auer)'s *The Discovery of the Nature Printing-Process*.

[Fern bars](/source/Fern_bar) were popular in America in the 1970s and 80s.

### Folklore

Ferns figure in folklore, for example in legends about mythical flowers or seeds.[72] In [Slavic folklore](/source/Slavic_folklore), ferns are believed to bloom once a year, during the [Ivan Kupala](/source/Ivan_Kupala_Day) night. Although alleged to be exceedingly difficult to find, anyone who sees a [fern flower](/source/Fern_flower) is thought to be guaranteed to be happy and rich for the rest of their life. Similarly, [Finnish](/source/Finland) tradition holds that one who finds the [seed](/source/Seed) of a fern in bloom on [Midsummer](/source/Midsummer) night will, by possession of it, be guided and be able to travel invisibly to the locations where eternally blazing [Will o' the wisps](/source/Will_o'_the_wisp) called *[aarnivalkea](/source/Aarnivalkea)* mark the spot of hidden [treasure](/source/Treasure). These spots are protected by a spell that prevents anyone but the fern-seed holder from ever knowing their locations.[73] In Wicca, ferns are thought to have magical properties such as a dried fern can be thrown into hot coals of a fire to exorcise evil spirits, or smoke from a burning fern is thought to drive away snakes and such creatures.[74]

### New Zealand

The [Silver fern](/source/Silver_fern) is the national emblem of New Zealand and feature on its passport and in the design of its national airline, [Air New Zealand](/source/Air_New_Zealand), and of its rugby team, the [All Blacks](/source/All_Blacks).[*[citation needed](https://en.wikipedia.org/wiki/Wikipedia:Citation_needed)*]

## Organisms confused with ferns

### Misnomers

Several non-fern plants (and even animals) are called ferns and are sometimes confused with ferns. These include:

- Asparagus fern — This may apply to one of several species of flowering plants in the [monocot](/source/Monocotyledon) genus *[Asparagus](/source/Asparagus_(genus))*.

- Sweetfern — A flowering shrub of the genus *[Comptonia](/source/Comptonia_(plant))*.

- [Air fern](/source/Air_fern) — A group of [animals](/source/Animal) called [hydrozoans](/source/Hydrozoa) that are distantly related to [jellyfish](/source/Jellyfish) and [corals](/source/Coral). They are harvested, dried, dyed green, and then sold as a plant that can live on air. While it may look like a fern, it is merely the skeleton of this [colonial animal](/source/Colony_(biology)).

- Fern bush — *[Chamaebatiaria millefolium](/source/Chamaebatiaria)*—a rose family shrub with fern-like leaves.

- Fern tree — *[Jacaranda mimosifolia](/source/Jacaranda_mimosifolia)*—an [ornamental tree](/source/Ornamental_tree) of the order [Lamiales](/source/Lamiales).

- Fern leaf tree — *[Filicium decipiens](/source/Filicium_decipiens)*—an [ornamental tree](/source/Ornamental_tree) of the order [Sapindales](/source/Sapindales).

### Fern-like flowering plants and gymnosperms

Some [flowering plants](/source/Flowering_plant) such as [palms](/source/Arecaceae) and members of the [carrot family](/source/Apiaceae) have [pinnate](/source/Pinnate) leaves that somewhat resemble fern fronds. However, these plants have fully developed seeds contained in fruits, rather than the microscopic spores of ferns.

[Cycads](/source/Cycad), which are [gymnosperms](/source/Gymnosperm) also have pinnate leaves that somewhat resemble fern fronds.

## See also

- [British Pteridological Society](/source/British_Pteridological_Society)

- [Chirosia betuleti](/source/Chirosia_betuleti) – Fern gall

- [Fern spike](/source/Fern_spike)

- [Fern sports](/source/Fern_sports)

- [Paisley (design)](/source/Paisley_(design))

- [Pteridophyte](/source/Pteridophyte)

- [Silver fern flag](/source/Silver_fern_flag)

## Notes

1. **[^](#cite_ref-39)** President, International Association of Pteridologists

## References

1. ^ [***a***](#cite_ref-FOOTNOTEStein_et_al2007_1-0) [***b***](#cite_ref-FOOTNOTEStein_et_al2007_1-1) [Stein et al 2007](#CITEREFStein_et_al2007).

1. ^ [***a***](#cite_ref-FOOTNOTEPteridophyte_Phylogeny_Group2016_2-0) [***b***](#cite_ref-FOOTNOTEPteridophyte_Phylogeny_Group2016_2-1) [***c***](#cite_ref-FOOTNOTEPteridophyte_Phylogeny_Group2016_2-2) [***d***](#cite_ref-FOOTNOTEPteridophyte_Phylogeny_Group2016_2-3) [***e***](#cite_ref-FOOTNOTEPteridophyte_Phylogeny_Group2016_2-4) [Pteridophyte Phylogeny Group 2016](#CITEREFPteridophyte_Phylogeny_Group2016).

1. ^ [***a***](#cite_ref-DK_Pub.-2017_3-0) [***b***](#cite_ref-DK_Pub.-2017_3-1) [***c***](#cite_ref-DK_Pub.-2017_3-2) [***d***](#cite_ref-DK_Pub.-2017_3-3) [***e***](#cite_ref-DK_Pub.-2017_3-4) ["Horsetails, clubmosses, and ferns"](https://archive.org/details/ultimate-visual-dictionary-by-dk-z-lib.org/page/120/mode/2up). *Ultimate Visual Dictionary* (11th ed.). [DK Pub.](/source/DK_Pub.) 2017. pp. 120–121. [ISBN](/source/ISBN_(identifier)) [978-1-4654-5894-0](https://en.wikipedia.org/wiki/Special:BookSources/978-1-4654-5894-0) – via Internet Archive.

1. **[^](#cite_ref-4)** Gerrienne, Philippe; Gonez, Paul (2011). ["Early evolution of life cycles in embryophytes: A focus on the fossil evidence of gametophyte/sporophyte size and morphological complexity"](https://doi.org/10.1111%2Fj.1759-6831.2010.00096.x). *Journal of Systematics and Evolution*. **49** (1): 1–16. [Bibcode](/source/Bibcode_(identifier)):[2011JSyEv..49....1G](https://ui.adsabs.harvard.edu/abs/2011JSyEv..49....1G). [doi](/source/Doi_(identifier)):[10.1111/j.1759-6831.2010.00096.x](https://doi.org/10.1111%2Fj.1759-6831.2010.00096.x).

1. ^ [***a***](#cite_ref-Polypodiopsida_5-0) [***b***](#cite_ref-Polypodiopsida_5-1) Nitta, Joel H.; Schuettpelz, Eric; Ramírez-Barahona, Santiago; Iwasaki, Wataru; et al. (2022). ["An Open and Continuously Updated Fern Tree of Life"](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9449725). *Frontiers in Plant Science*. **13** 909768. [Bibcode](/source/Bibcode_(identifier)):[2022FrPS...1309768N](https://ui.adsabs.harvard.edu/abs/2022FrPS...1309768N). [doi](/source/Doi_(identifier)):[10.3389/fpls.2022.909768](https://doi.org/10.3389%2Ffpls.2022.909768). [PMC](/source/PMC_(identifier)) [9449725](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9449725). [PMID](/source/PMID_(identifier)) [36092417](https://pubmed.ncbi.nlm.nih.gov/36092417).

1. **[^](#cite_ref-6)** Mauseth, James D. (September 2008). [*Botany: an Introduction to Plant Biology*](https://books.google.com/books?id=UEsBPPlxP7EC&pg=PA492). Jones & Bartlett Publishers. p. 492. [ISBN](/source/ISBN_(identifier)) [978-1-4496-4720-9](https://en.wikipedia.org/wiki/Special:BookSources/978-1-4496-4720-9).

1. ^ [***a***](#cite_ref-Levyns-1966_7-0) [***b***](#cite_ref-Levyns-1966_7-1) [***c***](#cite_ref-Levyns-1966_7-2) Levyns, M. R. (1966). *A Guide to the Flora of the Cape Peninsula* (2nd Revised ed.). Juta & Company. [OCLC](/source/OCLC_(identifier)) [621340](https://search.worldcat.org/oclc/621340).

1. **[^](#cite_ref-8)** Fernández, Helena; Kumar, Ashwani; Revilla, Maria Angeles (11 November 2010). [*Working with Ferns: Issues and Applications*](https://books.google.com/books?id=smtpBM7UgXEC&pg=PA175). Springer. p. 175. [ISBN](/source/ISBN_(identifier)) [978-1-4419-7162-3](https://en.wikipedia.org/wiki/Special:BookSources/978-1-4419-7162-3).

1. **[^](#cite_ref-9)** Hodgson, Larry (1 January 2005). [*Making the Most of Shade: How to Plan, Plant, and Grow a Fabulous Garden that Lightens Up the Shadows*](https://books.google.com/books?id=HDij6Fmk2MwC&pg=PA329). Rodale. p. 329. [ISBN](/source/ISBN_(identifier)) [978-1-57954-966-4](https://en.wikipedia.org/wiki/Special:BookSources/978-1-57954-966-4).

1. **[^](#cite_ref-FOOTNOTEMcCausland2019_10-0)** [McCausland 2019](#CITEREFMcCausland2019).

1. **[^](#cite_ref-Stace-2019_11-0)** [Stace, C. A.](/source/Stace%2C_C._A.) (2019). *New Flora of the British Isles* (Fourth ed.). Middlewood Green, Suffolk, U.K.: C & M Floristics. [ISBN](/source/ISBN_(identifier)) [978-1-5272-2630-2](https://en.wikipedia.org/wiki/Special:BookSources/978-1-5272-2630-2).

1. **[^](#cite_ref-12)** [Understanding the contribution of LFY and PEBP flowering genes to fern leaf dimorphism – Botany 2019](https://2019.botanyconference.org/engine/search/index.php?func=detail&aid=758).

1. **[^](#cite_ref-13)** [Fern Structure – Forest Service](https://www.fs.fed.us/wildflowers/beauty/ferns/structure.shtml).

1. **[^](#cite_ref-14)** [Fern Structure – Forest Service](https://www.nzplants.auckland.ac.nz/en/about/ferns/structure/frond.html), Auckland, New Zealand.

1. **[^](#cite_ref-15)** ["Fern Fronds"](https://web.archive.org/web/20150419003216/http://basicbiology.net/plants/ferns/fronds.php). Basic Biology. Archived from [the original](http://www.basicbiology.net/plants/ferns/fronds.php) on 19 April 2015. Retrieved 6 December 2014.

1. **[^](#cite_ref-16)** Large, Mark F.; [Braggins, John E.](/source/John_E._Braggins) (2004). [*Tree Ferns*](https://archive.org/details/treeferns00mark). Timber Press. [ISBN](/source/ISBN_(identifier)) [0-88192-630-2](https://en.wikipedia.org/wiki/Special:BookSources/0-88192-630-2).

1. **[^](#cite_ref-17)** Villareal A., Juan Carlos; Campos S., Laura Victoria; Urbide-M., Jaime; Goffinet, Bernard (2012). "Parallel Evolution of Endospory within Hornworts: *Nothoceros renzagliensis* (Dendrocerotaceae), sp. nov". *Systematic Botany*. **37** (1): 31–37. [Bibcode](/source/Bibcode_(identifier)):[2012SysBo..37...31V](https://ui.adsabs.harvard.edu/abs/2012SysBo..37...31V). [doi](/source/Doi_(identifier)):[10.1600/036364412X616594](https://doi.org/10.1600%2F036364412X616594).

1. **[^](#cite_ref-18)** Kelley, A.G.; Postlethwait, S.N. (1960). ["Fern Gametophytes as a Tool for the Study of Morphogenesis"](https://journals.indianapolis.iu.edu/index.php/ias/article/view/5459). *Proceedings of the Indiana Academy of Science*. **70**: 56–60. Retrieved 16 November 2025.

1. **[^](#cite_ref-19)** Allaby, Michael, ed. (2006). ["antherozoid"](https://www.oxfordreference.com/display/10.1093/acref/9780198608912.001.0001/acref-9780198608912-e-386). *A Dictionary of Plant Sciences* (2nd ed.). Oxford University Press. [ISBN](/source/ISBN_(identifier)) [9780191726804](https://en.wikipedia.org/wiki/Special:BookSources/9780191726804).

1. **[^](#cite_ref-20)** Jones, Victor A.S.; Dolan, Liam (2012). ["The evolution of root hairs and rhizoids"](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3394659). *Annals of Botany*. **110** (2): 205–212. [doi](/source/Doi_(identifier)):[10.1093/aob/mcs136](https://doi.org/10.1093%2Faob%2Fmcs136). [PMC](/source/PMC_(identifier)) [3394659](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3394659). [PMID](/source/PMID_(identifier)) [22730024](https://pubmed.ncbi.nlm.nih.gov/22730024).

1. **[^](#cite_ref-21)** Racusen, Richard H. (2002). ["Early Development in Fern Gametophytes: Interpreting the Transition to Prothallial Architecture in Terms of Coordinated Photosynthate Production and Osmotic Ion Uptake"](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4233796). *Annals of Botany*. **89** (2): 227–240. [doi](/source/Doi_(identifier)):[10.1093/aob/mcf032](https://doi.org/10.1093%2Faob%2Fmcf032). [PMC](/source/PMC_(identifier)) [4233796](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4233796). [PMID](/source/PMID_(identifier)) [12099354](https://pubmed.ncbi.nlm.nih.gov/12099354).

1. **[^](#cite_ref-22)** Quinlain, Alexandra; Lee, Pei-Hsuan; Tang, Te-Yen; Huang, Yao-Moan; Chiou, Wen-Liang; Kuo, Li-Yaung (2022). ["Providing the missing links in fern life history: Insights from a phenological survey of the gametophyte stage"](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9039788). *Applications in Plant Sciences*. **10** (2) e11473. [Bibcode](/source/Bibcode_(identifier)):[2022AppPS..10E1473Q](https://ui.adsabs.harvard.edu/abs/2022AppPS..10E1473Q). [doi](/source/Doi_(identifier)):[10.1002/aps3.11473](https://doi.org/10.1002%2Faps3.11473). [PMC](/source/PMC_(identifier)) [9039788](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9039788). [PMID](/source/PMID_(identifier)) [35495188](https://pubmed.ncbi.nlm.nih.gov/35495188).

1. **[^](#cite_ref-23)** [The Ferns (Filicales): Volume 1, Analytical Examination of the Criteria of Comparison: Treated Comparatively with a View to their Natural Classification](https://books.google.com/books?id=x494WF2PvbsC&pg=PA324)

1. **[^](#cite_ref-FOOTNOTEUnderwood1903_24-0)** [Underwood 1903](#CITEREFUnderwood1903).

1. **[^](#cite_ref-FOOTNOTELinnaeus1753_25-0)** [Linnaeus 1753](#CITEREFLinnaeus1753).

1. ^ [***a***](#cite_ref-FOOTNOTESchuettpelz_et_al2018_26-0) [***b***](#cite_ref-FOOTNOTESchuettpelz_et_al2018_26-1) [Schuettpelz et al 2018](#CITEREFSchuettpelz_et_al2018).

1. **[^](#cite_ref-FOOTNOTESwartz1806_27-0)** [Swartz 1806](#CITEREFSwartz1806).

1. ^ [***a***](#cite_ref-FOOTNOTEChristenhuszChase2014_28-0) [***b***](#cite_ref-FOOTNOTEChristenhuszChase2014_28-1) [***c***](#cite_ref-FOOTNOTEChristenhuszChase2014_28-2) [***d***](#cite_ref-FOOTNOTEChristenhuszChase2014_28-3) [Christenhusz & Chase 2014](#CITEREFChristenhuszChase2014).

1. ^ [***a***](#cite_ref-FOOTNOTESmith_et_al.2006_29-0) [***b***](#cite_ref-FOOTNOTESmith_et_al.2006_29-1) [***c***](#cite_ref-FOOTNOTESmith_et_al.2006_29-2) [***d***](#cite_ref-FOOTNOTESmith_et_al.2006_29-3) [***e***](#cite_ref-FOOTNOTESmith_et_al.2006_29-4) [***f***](#cite_ref-FOOTNOTESmith_et_al.2006_29-5) [Smith et al.2006](#CITEREFSmith_et_al.2006).

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## Bibliography

### Books

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- [Linnaeus, Carl](/source/Carl_Linnaeus) (1753). ["Cryptogamia: Filices Musci"](https://www.biodiversitylibrary.org/item/13830#page/503/mode/1up). [*Species Plantarum: exhibentes plantas rite cognitas, ad genera relatas, cum differentiis specificis, nominibus trivialibus, synonymis selectis, locis natalibus, secundum systema sexuale digestas*](https://www.biodiversitylibrary.org/bibliography/669#/summary). Vol. 1. Stockholm, Sweden: Impensis Laurentii Salvii. pp. 1061–1100, 1100–1130., *see also* [Species Plantarum](/source/Species_Plantarum)

- Lord, Thomas R. (2006). *Ferns and Fern Allies of Pennsylvania*. Indiana, Pennsylvania: Pinelands Press. [Ferns and Fern Allies of Pennsylvania – Thomas Reeves Lord](http://www.paferns.com/).

- Moran, Robbin C. (2004). *A Natural History of Ferns*. Portland, Oregon: Timber Press. [ISBN](/source/ISBN_(identifier)) [0-88192-667-1](https://en.wikipedia.org/wiki/Special:BookSources/0-88192-667-1)

- Ranker, Tom A.; Haufler, Christopher H. (2008). [*Biology and Evolution of Ferns and Lycophytes*](https://books.google.com/books?id=js9JnwEACAAJ). [Cambridge University Press](/source/Cambridge_University_Press). [ISBN](/source/ISBN_(identifier)) [978-0-521-87411-3](https://en.wikipedia.org/wiki/Special:BookSources/978-0-521-87411-3).

- [Swartz, Olof](/source/Olof_Swartz) (1806). [*Synopsis filicum: earum genera et species systematice complectens: adjectis lycopodineis, et descriptionibus novarum et rariorum specierum: cum tabulis aeneis quinque*](https://www.biodiversitylibrary.org/bibliography/81948#/summary). [Kiliae](/source/Kiliae): Impensis Bibliopolii novi academici.

### Journal articles

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- Bomfleur, B.; McLoughlin, S.; Vajda, V. (20 March 2014). ["Fossilized Nuclei and Chromosomes Reveal 180 Million Years of Genomic Stasis in Royal Ferns"](http://nrm.diva-portal.org/smash/get/diva2:719316/FULLTEXT01). *[Science](/source/Science_(journal))*. **343** (6177): 1376–1377. [Bibcode](/source/Bibcode_(identifier)):[2014Sci...343.1376B](https://ui.adsabs.harvard.edu/abs/2014Sci...343.1376B). [doi](/source/Doi_(identifier)):[10.1126/science.1249884](https://doi.org/10.1126%2Fscience.1249884). [PMID](/source/PMID_(identifier)) [24653037](https://pubmed.ncbi.nlm.nih.gov/24653037). [S2CID](/source/S2CID_(identifier)) [38248823](https://api.semanticscholar.org/CorpusID:38248823).

- Cantino, Philip D.; Doyle, James A.; Graham, Sean W.; [Judd, Walter S.](/source/Walter_S._Judd); Olmstead, Richard G.; [Soltis, Douglas E.](/source/Douglas_Soltis); [Soltis, Pamela S.](/source/Pamela_Soltis); [Donoghue, Michael J.](/source/Michael_Donoghue) (1 August 2007). "Towards a Phylogenetic Nomenclature of Tracheophyta". *[Taxon](/source/Taxon_(journal))*. **56** (3): 822. [doi](/source/Doi_(identifier)):[10.2307/25065865](https://doi.org/10.2307%2F25065865). [JSTOR](/source/JSTOR_(identifier)) [25065865](https://www.jstor.org/stable/25065865).

- [Chase, Mark W.](/source/Mark_W._Chase) & [Reveal, James L.](/source/James_L._Reveal) (2009). ["A phylogenetic classification of the land plants to accompany APG III"](https://doi.org/10.1111%2Fj.1095-8339.2009.01002.x). *[Botanical Journal of the Linnean Society](/source/Botanical_Journal_of_the_Linnean_Society)*. **161** (2): 122–127. [doi](/source/Doi_(identifier)):[10.1111/j.1095-8339.2009.01002.x](https://doi.org/10.1111%2Fj.1095-8339.2009.01002.x).

- [Christenhusz, Maarten J. M.](/source/Maarten_Christenhusz) & [Byng, J. W.](/source/James_W._Byng) (2016). ["The number of known plants species in the world and its annual increase"](http://biotaxa.org/Phytotaxa/article/download/phytotaxa.261.3.1/20598). *[Phytotaxa](/source/Phytotaxa)*. **261** (3). Magnolia Press: 201–217. [Bibcode](/source/Bibcode_(identifier)):[2016Phytx.261..201C](https://ui.adsabs.harvard.edu/abs/2016Phytx.261..201C). [doi](/source/Doi_(identifier)):[10.11646/phytotaxa.261.3.1](https://doi.org/10.11646%2Fphytotaxa.261.3.1).

- [Christenhusz, Maarten J. M.](/source/Maarten_J._M._Christenhusz); Zhang, X. C.; Schneider, H. (18 February 2011). ["A linear sequence of extant families and genera of lycophytes and ferns"](https://doi.org/10.11646%2Fphytotaxa.19.1.2). *[Phytotaxa](/source/Phytotaxa)*. **19** (1): 7. [Bibcode](/source/Bibcode_(identifier)):[2011Phytx..19....7C](https://ui.adsabs.harvard.edu/abs/2011Phytx..19....7C). [doi](/source/Doi_(identifier)):[10.11646/phytotaxa.19.1.2](https://doi.org/10.11646%2Fphytotaxa.19.1.2). [hdl](/source/Hdl_(identifier)):[10138/28042](https://hdl.handle.net/10138%2F28042).

- [Christenhusz, Maarten J. M.](/source/Christenhusz); [Chase, Mark W.](/source/Mark_W._Chase) (2014). ["Trends and concepts in fern classification"](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3936591). *[Annals of Botany](/source/Annals_of_Botany)*. **113** (4): 571–594. [doi](/source/Doi_(identifier)):[10.1093/aob/mct299](https://doi.org/10.1093%2Faob%2Fmct299). [PMC](/source/PMC_(identifier)) [3936591](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3936591). [PMID](/source/PMID_(identifier)) [24532607](https://pubmed.ncbi.nlm.nih.gov/24532607).

- [Christenhusz, Maarten J. M.](/source/Maarten_Christenhusz); [Chase, Mark W.](/source/Mark_W._Chase) (1 June 2018). ["PPG recognises too many fern genera"](https://doi.org/10.12705%2F673.2). *[Taxon](/source/Taxon_(journal))*. **67** (3): 481–487. [Bibcode](/source/Bibcode_(identifier)):[2018Taxon..67..481C](https://ui.adsabs.harvard.edu/abs/2018Taxon..67..481C). [doi](/source/Doi_(identifier)):[10.12705/673.2](https://doi.org/10.12705%2F673.2).

- May, Lenore Wile (1978). "The economic uses and associated folklore of ferns and fern allies". *[The Botanical Review](/source/The_Botanical_Review)*. **44** (4): 491–528. [Bibcode](/source/Bibcode_(identifier)):[1978BotRv..44..491M](https://ui.adsabs.harvard.edu/abs/1978BotRv..44..491M). [doi](/source/Doi_(identifier)):[10.1007/BF02860848](https://doi.org/10.1007%2FBF02860848). [S2CID](/source/S2CID_(identifier)) [42101599](https://api.semanticscholar.org/CorpusID:42101599).

- Melan, M. A.; Whittier, D. P. (1990). "Effects of Inorganic Nitrogen Sources on Spore Germination and Gametophyte Growth in Botrychium Dissectum". *Plant, Cell and Environment*. **13** (5): 477–482. [Bibcode](/source/Bibcode_(identifier)):[1990PCEnv..13..477M](https://ui.adsabs.harvard.edu/abs/1990PCEnv..13..477M). [doi](/source/Doi_(identifier)):[10.1111/j.1365-3040.1990.tb01325.x](https://doi.org/10.1111%2Fj.1365-3040.1990.tb01325.x).

- Pryer, Kathleen M.; Schneider, Harald; Smith, Alan R.; Cranfill, Raymond; Wolf, Paul G.; Hunt, Jeffrey S.; Sipes, Sedonia D. (2001). "Horsetails and ferns are a monophyletic group and the closest living relatives to seed plants". *Nature*. **409** (6820): 618–622. [Bibcode](/source/Bibcode_(identifier)):[2001Natur.409..618S](https://ui.adsabs.harvard.edu/abs/2001Natur.409..618S). [doi](/source/Doi_(identifier)):[10.1038/35054555](https://doi.org/10.1038%2F35054555). [PMID](/source/PMID_(identifier)) [11214320](https://pubmed.ncbi.nlm.nih.gov/11214320). [S2CID](/source/S2CID_(identifier)) [4367248](https://api.semanticscholar.org/CorpusID:4367248).

- Pryer, Kathleen M.; Schuettpelz, Eric; Wolf, Paul G.; Schneider, Harald; Smith, Alan R.; Cranfill, Raymond (2004). "Phylogeny and evolution of ferns (monilophytes) with a focus on the early leptosporangiate divergences". *American Journal of Botany*. **91** (10): 1582–1598. [Bibcode](/source/Bibcode_(identifier)):[2004AmJB...91.1582P](https://ui.adsabs.harvard.edu/abs/2004AmJB...91.1582P). [doi](/source/Doi_(identifier)):[10.3732/ajb.91.10.1582](https://doi.org/10.3732%2Fajb.91.10.1582). [PMID](/source/PMID_(identifier)) [21652310](https://pubmed.ncbi.nlm.nih.gov/21652310).

- Pteridophyte Phylogeny Group (November 2016). ["A community-derived classification for extant lycophytes and ferns"](https://doi.org/10.1111%2Fjse.12229). *Journal of Systematics and Evolution*. **54** (6): 563–603. [Bibcode](/source/Bibcode_(identifier)):[2016JSyEv..54..563.](https://ui.adsabs.harvard.edu/abs/2016JSyEv..54..563.). [doi](/source/Doi_(identifier)):[10.1111/jse.12229](https://doi.org/10.1111%2Fjse.12229). [S2CID](/source/S2CID_(identifier)) [39980610](https://api.semanticscholar.org/CorpusID:39980610).

- Schneider, Harald; Smith, Alan R.; Pryer, Kathleen M. (1 July 2009). "Is Morphology Really at Odds with Molecules in Estimating Fern Phylogeny?". *[Systematic Botany](/source/Systematic_Botany)*. **34** (3): 455–475. [Bibcode](/source/Bibcode_(identifier)):[2009SysBo..34..455S](https://ui.adsabs.harvard.edu/abs/2009SysBo..34..455S). [doi](/source/Doi_(identifier)):[10.1600/036364409789271209](https://doi.org/10.1600%2F036364409789271209). [S2CID](/source/S2CID_(identifier)) [85855934](https://api.semanticscholar.org/CorpusID:85855934).

- Schuettpelz, Eric (2007). "Table 1". [*The evolution and diversification of epiphytic ferns*](https://web.archive.org/web/20100620022844/http://dukespace.lib.duke.edu/dspace/bitstream/10161/181/1/D_Schuettpelz_Eric_a_052007.pdf) (PDF) ([PhD thesis](/source/PhD_thesis)). [Duke University](/source/Duke_University). Archived from [the original](http://dukespace.lib.duke.edu/dspace/bitstream/10161/181/1/D_Schuettpelz_Eric_a_052007.pdf) (PDF) on 20 June 2010. Retrieved 11 December 2009.

- Schuettpelz, Eric; Rouhan, Germinal; Pryer, Kathleen M.; Rothfels, Carl J.; Prado, Jefferson; Sundue, Michael A.; Windham, Michael D.; Moran, Robbin C.; Smith, Alan R. (1 June 2018). ["Are there too many fern genera?"](https://doi.org/10.12705%2F673.1). *[Taxon](/source/Taxon_(journal))*. **67** (3): 473–480. [Bibcode](/source/Bibcode_(identifier)):[2018Taxon..67..473S](https://ui.adsabs.harvard.edu/abs/2018Taxon..67..473S). [doi](/source/Doi_(identifier)):[10.12705/673.1](https://doi.org/10.12705%2F673.1).

- Smith, Alan R.; Kathleen M. Pryer; Eric Schuettpelz; Petra Korall; Harald Schneider; Paul G. Wolf (2006). ["A classification for extant ferns"](https://www.idigbio.org/wiki/images/9/95/Smith_et_al_2006.pdf) (PDF). *[Taxon](/source/Taxon_(journal))*. **55** (3): 705–731. [Bibcode](/source/Bibcode_(identifier)):[2006Taxon..55..705S](https://ui.adsabs.harvard.edu/abs/2006Taxon..55..705S). [doi](/source/Doi_(identifier)):[10.2307/25065646](https://doi.org/10.2307%2F25065646). [JSTOR](/source/JSTOR_(identifier)) [25065646](https://www.jstor.org/stable/25065646).

- Stein, W. E.; Mannolini, F.; Hernick, L. V.; Landling, E.; Berry, C. M. (2007). "Giant cladoxylopsid trees resolve the enigma of the Earth's earliest forest stumps at Gilboa". *[Nature](/source/Nature_(journal))*. **446** (7138): 904–907. [Bibcode](/source/Bibcode_(identifier)):[2007Natur.446..904S](https://ui.adsabs.harvard.edu/abs/2007Natur.446..904S). [doi](/source/Doi_(identifier)):[10.1038/nature05705](https://doi.org/10.1038%2Fnature05705). [PMID](/source/PMID_(identifier)) [17443185](https://pubmed.ncbi.nlm.nih.gov/17443185). [S2CID](/source/S2CID_(identifier)) [2575688](https://api.semanticscholar.org/CorpusID:2575688).

- Walkowiak, Radoslaw Janusz (2017). ["Classification of Pteridophytes – Short classification of the ferns"](https://internationalequisetologicalassociation.yolasite.com/resources/Classification%20of%20Pteridophytes.pdf) (PDF). *IEA Paper*. [doi](/source/Doi_(identifier)):[10.13140/RG.2.2.29934.20809](https://doi.org/10.13140%2FRG.2.2.29934.20809).

- Underwood, L. M. (1903). "The early writers on ferns and their collections. I. Linnaeus, 1707–1778". *[Torreya](/source/Torrey_Botanical_Society)*. **3** (10): 145–150. [ISSN](/source/ISSN_(identifier)) [0096-3844](https://search.worldcat.org/issn/0096-3844). [JSTOR](/source/JSTOR_(identifier)) [40594126](https://www.jstor.org/stable/40594126).

### Websites

- McCausland, Jim (22 February 2019). ["Rediscover ferns"](https://web.archive.org/web/20211030104351/https://www.sunset.com/garden/flowers-plants/rediscover-ferns). *Garden plants*. Sunset Magazine. Archived from [the original](https://www.sunset.com/garden/flowers-plants/rediscover-ferns) on 30 October 2021. Retrieved 22 November 2019.

- ["Pteridopsida: Fossil Record"](http://www.ucmp.berkeley.edu/plants/pterophyta/pteridofr.html). *Plants: Pteridopsida*. [University of California Museum of Paleontology](/source/University_of_California_Museum_of_Paleontology). Retrieved 23 November 2019.

- ["Classifying and identifying ferns"](https://www.sciencelearn.org.nz/resources/1104-classifying-and-identifying-ferns). *Science Learning Hub*. [The University of Waikato](/source/The_University_of_Waikato). 3 September 2018. Retrieved 24 November 2019.

- Mickel, John T.; Wagner, Warren H.; Gifford, Ernest M.; et al. (4 February 2019). ["Fern"](https://www.britannica.com/plant/fern). *[Encyclopædia Britannica](/source/Encyclop%C3%A6dia_Britannica)*. Retrieved 24 November 2019.

- Hassler, Michael; Schmitt, Bernd (2 November 2019). ["Checklist of Ferns and Lycophytes of the World"](https://web.archive.org/web/20170902225743/http://worldplants.webarchiv.kit.edu/ferns/). *World Ferns*. [Botanical Garden of the Karlsruhe Institute of Technology](/source/Botanical_Garden_of_the_Karlsruhe_Institute_of_Technology). Archived from [the original](https://worldplants.webarchiv.kit.edu/ferns/) on 2 September 2017. Retrieved 25 November 2019.

- Pryer, Kathleen M.; Smith, Alan R.; Rothfels, Carl (2009). ["Polypodiopsida"](http://tolweb.org/Polypodiopsida/20615). *[Tree of Life](/source/Tree_of_Life)*.

- [*A classification of the ferns and their allies*.](https://web.archive.org/web/20160304060354/http://www.anbg.gov.au/fern/taxa/classification.html) (Australian National Herbarium)

- [*A fern book bibliography*.](https://web.archive.org/web/20160117055319/http://www.jaknouse.athens.oh.us/ferns/bookfern.html)

- [Register of fossil Pteridophyta](https://web.archive.org/web/20080509142839/http://www1.akira.ne.jp/~unzen/pteridophyta.html)

- [Watson, L. and M. J. Dallwitz (2004 onwards). *The Ferns (Filicopsida) of the British Isles*.](http://delta-intkey.com/britfe/) [Archived](https://web.archive.org/web/20160303183034/http://delta-intkey.com/britfe/) 3 March 2016 at the [Wayback Machine](/source/Wayback_Machine)

- [*Ferns and Pteridomania in Victorian Scotland*.](http://www.peterboyd.com/pteridomania2.htm)

- [Non-seed plant images at *bioimages.vanderbilt.edu*](https://web.archive.org/web/20120512162340/http://www.cas.vanderbilt.edu/bioimages/pages/non-seed-plants.htm)

- [American Fern Society](http://www.amerfernsoc.org/)

- [British Pteridological Society](http://www.eBPS.org.uk/) [Archived](https://web.archive.org/web/20190102094708/https://ebps.org.uk/) 2 January 2019 at the [Wayback Machine](/source/Wayback_Machine)

- [International Equisetological Association](http://internationalequisetologicalassociation.yolasite.com/)

v t e Botany History Outline Subdisciplines Archaeobotany Astrobotany Bryology Dendrology Ethnobotany Paleobotany Phycology Phytochemistry Phytogeography Geobotany Plant anatomy Plant ecology Plant intelligence Plant pathology Plant physiology Plant groups Algae Archaeplastida Bryophyte Non-vascular plants Vascular plants Fern Lycophyte Spermatophytes Gymnosperm Angiosperm Plant anatomy Plant morphology (glossary) Plant cells Cell wall Phragmoplast Plastid Plasmodesma Vacuole Tissues Cork Ground tissue Mesophyll Meristem Storage organs Vascular tissue Vascular bundle Wood Vegetative Bulb Root Rhizoid Rhizome Shoot Bud Leaf Cataphyll Petiole Sessility Stem Reproductive (incl. Flower) Archegonium Antheridium Androecium Pollen Stamen Anther Filament Staminode Tapetum Flower Aestivation Flower development Floral diagram Floral formula Floral symmetry Whorl Fruit Anatomy Berry Capsule Nut Pyrena Seed Dispersal Endosperm Gametophyte Gynandrium Gynoecium Carpel Ovary Locule Ovule Stigma Style Hypanthium (Floral cup) Inflorescence Bract Pedicellate Raceme Umbel Perianth Tepal Petal Sepal Plant embryo Receptacle Sporophyll Sporophyte Surface structures Cuticle Epicuticular wax Epidermis Nectar Stoma Thorns, spines, and prickles Trichome Plant physiology Materials Aleurone Apical dominance Bulk flow Cellulose Nutrition Photosynthesis Chlorophyll Phytomelanin Plant hormones Respiration Gas Exchange Cellular respiration Sap Starch Sugar Transpiration Turgor pressure Plant growth and habit Habit Cushion plants Rosettes Shrubs Prostrate shrubs Subshrubs Succulent plants Trees Vines Lianas Herbaceous plants Secondary growth Woody plants Reproduction Evolution Ecology Alternation of generations Double fertilization Evolutionary development Evolutionary history timeline Flora Germination Pollination Artificial Pollinators Pollen tube Self Sporangium Microsporangia Microspore Megasporangium Megaspore Spore Plant taxonomy Biological classification Botanical nomenclature Botanical name Correct name Author citation International Code of Nomenclature (ICN) ICN for Cultivated Plants (ICNCP) Cultivated plant taxonomy Citrus taxonomy Cultigen Cultivar Group Grex History of plant systematics Herbarium International Association for Plant Taxonomy (IAPT) Plant taxonomy systems Taxonomic rank Practice Agronomy Floriculture Forestry Horticulture Phytochemical Lists Related Botanical terms Botanists by author abbreviation Botanical expeditions Individual trees Oldest trees Superlative trees Tallest trees Plants Category

v t e Classification of Archaeplastida or Plantae s.l. Domain Archaea Bacteria Eukaryota (major groups Metamonada Discoba Diaphoretickes Hacrobia Cryptista Rhizaria Alveolata Stramenopiles Plants Amorphea Amoebozoa Opisthokonta Animalia Fungi Mesomycetozoea) incertae sedis †Algospongia Glaucoplantae Glaucophyta Glaucocystophyceae Rhodoplantae Picozoa Picomonadea Rhodelphidia Rhodelphea Rhodophyta (red algae) Cyanidiophytina Cyanidiophyceae Proteorhodophytina Porphyridiophyceae Stylonematophyceae Compsopogonophyceae Rhodellophyceae Eurhodophytina Bangiophyceae Florideophyceae Viridiplantae or Plantae s.s. (green algae & land plants) Prasinodermophyta Prasinodermophyceae Palmophyllophyceae Chlorophyta Prasinophytina Mamiellophyceae Pyramimonadophyceae Chlorophytina Nephroselmidophyceae Picocystophyceae Chloropicophyceae Pedinophyceae Chlorodendrophyceae UTC clade Ulvophyceae Trebouxiophyceae Chlorophyceae Streptophyta Chlorokybophytina Mesostigmatophyceae Chlorokybophyceae Spirotaeniaceae Klebsormidiophytina Klebsormidiophyceae Phragmoplastophyta Charophytina Charophyceae Coleochaetophytina Coleochaetophyceae Anydrophyta Zygnematophytina Zygnematophyceae Embryophyta (land plants) Bryophytes Marchantiophyta (liverworts) Haplomitriopsida Marchantiopsida Jungermanniopsida Anthocerotophyta (hornworts) Leiosporocerotopsida Anthocerotopsida Bryophyta (mosses) Takakiopsida Sphagnopsida Andreaeobryopsida Andreaeopsida Oedipodiopsida Tetraphidopsida Polytrichopsida Bryopsida Polysporangiophytes †Protracheophytes* †Aglaophyton †Eophytidae †Horneophytopsida Tracheophytes (vascular plants) †Paratracheophytes* †Cooksoniopsida †Renaliales †Rhyniopsida Eutracheophytes Lycophytes †Barinophytopsida †Zosterophyllopsida Lycopodiopsida (clubmosses, spikemosses & quillworts) Euphyllophytes †Eophyllophytopsida †Trimerophytopsida Moniliformopses †Ibykales †Cladoxylopsida Polypodiopsida (ferns and horsetails) Lignophytes †Progymnosperms* †Aneurophytopsida †Archaeopteridopsida †Noeggerathiopsida †Protopityales Spermatophytes (seed plants) †Pteridosperms* (seed ferns) and other extinct seed plant groups †Bennettitales †Calamopityales †Callistophytales †Caytoniales †Cordaitales †Corystospermales †Czekanowskiales †Gigantopteridales †Glossopteridales †Lyginopteridopsida †Medullosales †Peltaspermopsida †Pentoxylopsida †Petriellales Acrogymnospermae (living gymnosperms) Cycadopsida (cycads) Ginkgoales (Ginkgo) Pinopsida (conifers) Gnetopsida Angiospermae (flowering plants) Basal angiosperms Core angiosperms Magnoliids Monocots Eudicots *paraphyletic groups † = extinct List of plant orders Current definitions of Plantae

v t e Fern classification Kingdom Plant: Rhodophyta Chlorophyta Marchantiophyta Bryophyta Anthocerotophyta Polypodiophyta Acrogymnospermae Angiospermae Basal clade †Ibykales †Ibykaceae †Cladoxylopsida †Cladoxylales †Cladoxylaceae †Voelkeliaceae †Hyeniales †Hyeniaceae †Iridopteridales †Iridopteridaceae †Pseudosporochnales †Pseudosporochnaceae †Steloxylales †Steloxylaceae Polypodiopsida †Stauropterididae †Stauropteridales †Stauropteridaceae †Zygopterididae †Rhacophytales †Rhacophytaceae †Zygopteridales †Zygopteridaceae Equisetidae †Pseudoborniales †Pseudoborniaceae †Sphenophyllales †Aspidostachyaceae †Boegendorfiaceae †Boegendorfiaceae †Eviostachyaceae †Sphenophyllaceae Equisetales †Asterocalamitaceae †Autophyllitaceae †Honseleriaceae †Archaeocalamitaceae †Paracalamitaceae †Calamitaceae †Apocalamitaceae †Konnostachyaceae †Manchurostachyaceae †Notocalamitaceae †Schizoneuraceae †Sorocaulinaceae †Echinostachyaceae †Gondwanostachyaceae †Tchernoviaceae Equisetaceae Ophioglossidae Psilotales Psilotaceae Ophioglossales Ophioglossaceae Marattiidae Marattiales †Knorripteridaceae †Pecopteridaceae †Ptychocarpaceae †Weichseliaceae †Asterothecaceae †Danaeopsidaceae Marattiaceae Polypodiidae †Anachoropteridales †Anachoropteridaceae †Psalixochlaenaceae †Sermayaceae †Botryopteridiales †Botryopteridiaceae †Senftenbergiales †Senftenbergiaceae †Urnatopteridales †Crossothecaceae †Discopteridaceae †Urnatopteridaceae Osmundales †Guaireaceae Osmundaceae Hymenophyllales Hymenophyllaceae Gleicheniales †Oligocarpiaceae Dipteridaceae Gleicheniaceae Matoniaceae Schizaeales †Acrostichopteridaceae †Cynepteridaceae †Klukiaceae †Stachypteridaceae †Tempskyaceae Anemiaceae Lygodiaceae Schizaeaceae Salviniales †Heroleandraceae Marsileaceae †Hydropteridiaceae Salviniaceae Cyatheales Thyrsopteridineae Thyrsopteridaceae Loxsomataceae Plagiogyriaceae Culcitaceae Cyatheineae †Tanydoraceae Metaxyaceae Cibotiaceae Dicksoniaceae Cyatheaceae Polypodiales Saccolomatineae Saccolomataceae Lindsaeineae Cystodiaceae Lonchitidaceae Lindsaeaceae Pteridineae Pteridaceae Dennstaedtiineae Dennstaedtiaceae Aspleniineae Cystopteridaceae Rhachidosoridaceae Diplaziopsidaceae Hemidictyaceae Desmophlebiaceae Aspleniaceae Thelypteridaceae Woodsiaceae Onocleaceae Blechnaceae Athyriaceae Polypodiineae Hypodematiaceae Didymochlaenaceae Dryopteridaceae Lomariopsidaceae Nephrolepidaceae Tectariaceae Oleandraceae Davalliaceae Polypodiaceae

Taxon identifiers Polypodiophyta Wikidata: Q98522578 ITIS: 500003 Paleobiology Database: 263732

Authority control databases International GND FAST National United States France BnF data Japan Czech Republic Israel Other Yale LUX

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Adapted from the Wikipedia article [Fern](https://en.wikipedia.org/wiki/Fern) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Fern?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.