Pteridaceae is a large family of ferns in the order Pteridales. Members of the family have creeping or erect rhizomes and are mostly terrestrial or epipetric (growing on rock). The leaves are almost always compound and have linear sori that are typically on the margins of the leaves and lack a true indusium, typically being protected by a false indusium formed from the reflexed margin of the leaf. The family includes four groups of genera that are sometimes recognized as separate families: the adiantoid, cheilanthoid, pteroid, and hemionitidoid ferns. Relationships among these groups remain unclear, and although some recent genetic analyses of the Pteridales suggest that neither the family Pteridaceae nor the major groups within it are all monophyletic, as yet these analyses are insufficiently comprehensive and robust to provide good support for a revision of the order at the family level.

Contents 1 Traditional groups 2 Subfamilies 3 Phylogenic relationships 4 References 5 External links

Traditional groups

As traditionally defined, the groups within Pteridaceae are as follows:

• Adiantoid ferns (tribe Adianteae Gaudich. 1829^[2]); epipetric, terrestrial or epiphytic in moist habitats, rachis often dichotomously branching; sori relatively small and discrete with sproangia born on the false indusium rather than the leaf blade proper; only one genus:
  • Adiantum L. – maidenhair ferns^[3][4]

• Cheilanthoid ferns; primarily epipetric in semiarid habitats; leaves mostly with well-developed scales or trichomes, often bipinnate or otherwise highly compound; sporangia mostly born in marginal sori with false indusia that are +/- continuous around the leaf margins; several genera, including:
  • Argyrochosma (J.Sm.) Windham – false cloak ferns
  • Aspidotis (Nutt. ex Hook.) Copel. – lace ferns
  • Astrolepis D.M.Benham & Windham – cloak ferns
  • Cheilanthes Sw. – lip ferns
  • Notholaena R.Br. – cloak ferns
  • Pellaea Link – cliff brakes^[3][4]

• Pteridoid ferns (tribe Pterideae J. Sm 1841^[5]); terrestrial and epipetric in moist habitats; leaves mostly without prominent scales or trichomes, most often pinnate but sometimes more compound; sporangia born in marginal sori with false indusia that are +/- continuous around the leaf margins; several genera, including:
  • Pteris L. – brakes
  • Onychium Kaulf.^[3][4]

• Parkerioid ferns (tribe Parkerieae Brongn. 1843^[6]); aquatic in swamps and/or mangroves, including:
  • Acrostichum L. – leather ferns
  • Ceratopteris Brongn.^[3][4]

• Hemionitidoid ferns; terrestrial, epipetric or epiphytic in moist or semiarid habitats; leaves simple, pinnate, or more compound; sporangia born in linear non-marginal, exindusiate sori or sometimes in marginal sori; several genera, including:
  • Anogramma Link
  • Cryptogramma R.Br. – rock brakes
  • Eriosorus Fée
  • Hemionitis L.
  • Jamesonia Hook. & Grev.
  • Pityrogramma Link – gold ferns^[3][4]

• Vittarioid ferns (tribe Vittarieae C. Presl 1836^[7]); primarily epiphytic in tropical regions and all have simple leaves with sori that follow the veins and lack true indusia:
  • Anetium Splitg. 1840
  • Antrophyum Kaulf. 1875
  • Hecistopteris (L.) Sm. 1842
  • Monogramma Comm. ex Schkuhr 1809
  • Vittaria (L.) Sm. 1793 – Shoestring fern

Subfamilies

Based on phylogenetic research, Christenhusz et al. (2011) divided the Pteridaceae genera into the following subfamilies.^[8] These roughly correspond with the groups listed above, with the main difference being that adiantoid and vittarioid ferns are combined under the Vittarioideae subfamily name.

• Cryptogrammoideae S.Linds. 2009

Genera: Coniogramme, Cryptogramma, Llavea

• Ceratopteridoideae (J.Sm.) R.M.Tryon 1986

Genera: Acrostichum, Ceratopteris

• Pteridoideae C.Chr. ex Crabbe, Jermy & Mickel 1975

Genera: Actiniopteris, Anogramma, Aspleniopsis, Austrogramme, Cerosora, Cosentinia, Jamesonia, Nephopteris, Onychium, Pityrogramma, Pteris, Pterozonium, Syngramma, Taenitis

• Cheilanthoideae W.C.Shieh 1973

Genera: Adiantopsis, Aleuritopteris, Argyrochosma, Aspidotis, Astrolepis, Bommeria, Calciphilopteris, Cassebeera, Cheilanthes, Cheiloplecton, Doryopteris, Hemionitis, Mildella, Notholaena, Paraceterach, Paragymnopteris, Pellaea, Pentagramma, Trachypteris, Tryonella

• Vittarioideae (C.Presl) Crabbe, Jermy & Mickel 1975

Genera: Adiantum, Ananthacorus, Anetium, Antrophyum, Haplopteris, Hecistopteris, Monogramma, Polytaenium, Radiovittaria, Rheopteris, Scoliosorus, Vittaria

Phylogenic relationships

The following phylogram, showing the relationships between the subfamilies listed above, is based on Schuettpelz & Pryer (2008).^[9]

Pteridaceae	Cryptogrammoideae Ceratopteridoideae Pteridoideae Cheilanthoideae Vittarioideae

References

External links

Media related to Pteridaceae at Wikimedia Commons Data related to Pteridaceae at Wikispecies

• Tree of Life: Pteridaceae