Overview

Brief Summary

Introduction

Pteridaceae are one of the largest fern families, comprising over 1000 species (~10% of extant ferns). But even more notable than their species richness is the remarkable morphological and ecological diversity of the family, which includes obligate epiphytes, free-floating aquatics, brackish-swamp dwellers, several clades specialized for colonizing rocky deserts, and many generalist understory species. While some of these life forms do appear in other fern lineages (many other families, for example, contain epiphytes), most are rare and no other fern family contains such a wide range of ecological specializations.

Pteridaceae have been the subject of much taxonomic disagreement—their members have been distributed among at least 20 different families: Acrostichaceae; Actiniopteridaceae; Adiantaceae; Anopteraceae; Antrophyaceae; Bommeriaceae; Ceratopteridaceae; Cheilanthaceae; Coniogrammaceae; Crytopgrammaceae; Hemionitidaceae; Llaveaceae; Negripteridaceae; Notholaenaceae; Parkeriaceae; Platyzomataceae; Pteridaceae; Sinopteridaceae; Taenitidaceae; and Vittariaceae (Smith et al. 1996; Hassler and Swale, 2003). Some of these former family designations (e.g., Llaveaceae, Parkeriaceae, and Vittariaceae) correspond to monophyletic groups now known to be nested within the broader Pteridaceae, while others (e.g., Taenitidaceae) are assemblages of more distantly related species (Schuettpelz et al., 2007).

Trusted

Article rating from 0 people

Average rating: 2.5 of 5

Comprehensive Description

Description

Terrestrial, epilithic or (rarely) epiphytic ferns with a short life cycle or perennial. Rhizomes short or long, suberect, decumbent or creeping, often laterally branched; roots few or many, often fleshy. Stipe not articulated, often dark-coloured. Fronds tufted or widely spaced, mono- or dimorphic. Lamina pinnately compound, pedate, dichotomously forked or helicoid, often with a proliferating bud at the rhachis apex, herbaceous or coriaceous, glabrous or variously det with indumentum; ultimate segments often articulated; venation free (in sterile fronds) or forming a network, without included veinlets, ending in or near the margin, often in hydathodes. Indumentum composed of unicellular glands on the abaxial surface of the lamina, or needle-like hairs occuring on the axes and lamina and/or scales on the rhizome and stipe. Sori variously arranged, exindusiate or covered by a strongly modified marginal indusium. Sporangia often mixed with paraphyses (sterile hairs).
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© Mark Hyde, Bart Wursten and Petra Ballings

Source: Flora of Zimbabwe

Trusted

Article rating from 0 people

Average rating: 2.5 of 5

Description

Aquatic or semi-aquatic fern; rooted or free floating plants that complete their life cycle in a vry short time. Rhizome short erect; roots few arising from near the stipe base, with scales. Stipes green, succulent. Fronds tufted, dimorphic: fertile fronds larger, more dissected and with narrower linear segments than the sterile fronds; the fertile fronds often proliferous. Lamina pinnately compound, hebaceous, glabrous; venation forming a network, without included veinlets. Sporangia borne on the ultimate segments, solitary along the veins, within the reflexed margins.
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© Mark Hyde, Bart Wursten and Petra Ballings

Source: Flora of Zimbabwe

Trusted

Article rating from 0 people

Average rating: 2.5 of 5

"Pteroids" vs. "Pteridoids"

Note that the term “pteroid” is colloquial shorthand to refer to members of the Pteridaceae, whereas “pteridoid” refers to members of a specific Pteridaceae subclade.

Trusted

Article rating from 0 people

Average rating: 2.5 of 5

Characteristics

Perhaps due to the group's ecological breadth, Pteridaceae lack clear, unique, morphological features that unite their constituent species. One of the best characteristics is that members of this family never have true indusia—outgrowths of the lower leaf surface that protect the sporangia—although they frequently have modified leaf edges that serve the same function. These recurved leaf margins are sometimes strongly differentiated from the rest of the leaf tissue, and are thus referred to as “false indusia.”

Left: Abaxial leaf surfaces of Adiantum poiretii, showing sori and false indusia. © 2008 Carl Rothfels. Center: Fertile sporophyte of Coniogramme sp., showing sporangia distributed along the veins on the underside of the leaf. © 2007 Michael Sundue. Right: Naked sporangia arranged along the veins of the leaf of Hemionitis palmata. © 2004 Robbin Moran

Instead of the round or elongate sori (clusters of sporangia) that are typical of many ferns, members of the Pteridaceae usually have their sporangia distributed along the veins on the underside of the leaf, often in marginal coenosori (a more-or-less contiguous line of sporangia around the margin of the leaf). More rarely, the sporangia may be attached to the false indusium itself (Adiantum), or spread evenly across the undersurface of the leaf (Acrostichum). In addition to these macromorphological characteristics, members of the Pteridaceae tend to share a chromosome base number of x=30 (occasionally x=27, 28, or 29).

Trusted

Article rating from 0 people

Average rating: 2.5 of 5

Evolution and Systematics

Evolution

Discussion of Phylogenetic Relationships

View Pteridaceae Tree

Plastid DNA sequence data suggest that the Pteridaceae comprise five (mostly) well-supported clades (Schuettpelz et al., 2007). The cheilanthoids are sister to the adiantoids (which include both Adiantum and the group formerly referred to as the Vittariaceae); these two clades are together sister to the pteridoids plus the ceratopteroids; and the cryptogrammoids are, in turn, sister to this large clade. Of these five clades, only the cheilanthoids lack strong support, due to some uncertainty about the phylogenetic position of their earliest-diverging branch (the Doryopteris ludens clade—see the cheilanthoid page). These five clades, none of which correspond perfectly with previously recognized families or subfamilies, do show some ecological differentiation. The ceratopteroids contain the aquatic taxa; the pteridoids contain most of the generalist forest understory species; and the cheilanthoids contain most of the xeric habitat specialists.

This phylogenetic structure differs from the most recent formal taxonomic treatments of the family (Kramer, 1990; Tryon et al., 1990), which recognized two families (Pteridaceae and Vittariaceae), and divided the Pteridaceae into six subfamilies: Adiantoideae, Ceratopteridoideae, Cheilanthoideae, Platyzomatoideae, Pteridoideae, and Taenitidoideae. Molecular data demonstrate that the Vittariaceae are nested within Pteridaceae (specifically within the adiantoid clade), and, while the circumscriptions may be close in some cases, none of the formally described subfamilies of Tryon and Tryon (1990; Adiantoideae, Cheilanthoideae, etc.) corresponds perfectly to the informal clades recognized here (adiantoids, cheilanthoids, etc.). A formal revision of Pteridaceae awaits further data.

Trusted

Article rating from 0 people

Average rating: 2.5 of 5

Molecular Biology and Genetics

Molecular Biology

Statistics of barcoding coverage

Barcode of Life Data Systems (BOLD) Stats
                                        
Specimen Records:630Public Records:449
Specimens with Sequences:595Public Species:219
Specimens with Barcodes:576Public BINs:0
Species:244         
Species With Barcodes:235         
          
Creative Commons Attribution 3.0 (CC BY 3.0)

© Barcode of Life Data Systems

Source: Barcode of Life Data Systems (BOLD)

Trusted

Article rating from 0 people

Average rating: 2.5 of 5

Statistics of barcoding coverage

Barcode of Life Data Systems (BOLD) Stats
                                        
Specimen Records:466Public Records:432
Specimens with Sequences:459Public Species:204
Specimens with Barcodes:456Public BINs:0
Species:207         
Species With Barcodes:204         
          
Creative Commons Attribution 3.0 (CC BY 3.0)

© Barcode of Life Data Systems

Source: Barcode of Life Data Systems (BOLD)

Trusted

Article rating from 0 people

Average rating: 2.5 of 5

Barcode data

Creative Commons Attribution 3.0 (CC BY 3.0)

© Barcode of Life Data Systems

Source: Barcode of Life Data Systems (BOLD)

Trusted

Article rating from 0 people

Average rating: 2.5 of 5

Barcode data

Creative Commons Attribution 3.0 (CC BY 3.0)

© Barcode of Life Data Systems

Source: Barcode of Life Data Systems (BOLD)

Trusted

Article rating from 0 people

Average rating: 2.5 of 5

Locations of barcode samples

Collection Sites: world map showing specimen collection locations for Adiantaceae

Creative Commons Attribution 3.0 (CC BY 3.0)

© Barcode of Life Data Systems

Source: Barcode of Life Data Systems (BOLD)

Trusted

Article rating from 0 people

Average rating: 2.5 of 5

Locations of barcode samples

Collection Sites: world map showing specimen collection locations for Pteridaceae

Creative Commons Attribution 3.0 (CC BY 3.0)

© Barcode of Life Data Systems

Source: Barcode of Life Data Systems (BOLD)

Trusted

Article rating from 0 people

Average rating: 2.5 of 5

Wikipedia

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.

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)[1] included Adiantaceae as part of the family Pteridaceae and Christenhusz et al. (2011)[2] listed its genera in Vittarioideae (C.Presl) Crabbe, Jermy & Mickel 1975, one of five subfamilies of Pteridaceae.

Sources

Creative Commons Attribution Share Alike 3.0 (CC BY-SA 3.0)

Source: Wikipedia

Unreviewed

Article rating from 0 people

Average rating: 2.5 of 5

Pteridaceae

Pteridaceae is a large family of ferns in the order Polypodiales.[2] 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

Traditional groups

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

  • Adiantoid ferns (tribe Adianteae Gaudich. 1829[3]); epipetric, terrestrial or epiphytic in moist habitats, rachis often dichotomously branching; sori relatively small and discrete with sporangia born on the false indusium rather than the leaf blade proper; only one genus:
  • 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:
  • Pteridoid ferns (tribe Pterideae J. Sm 1841[6]); 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:
  • 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:
  • Vittarioid ferns (tribe Vittarieae C. Presl 1836[8]); primarily epiphytic in tropical regions and all have simple leaves with sori that follow the veins and lack true indusia:

Subfamilies

Based on phylogenetic research, Christenhusz et al. (2011) divided the Pteridaceae genera into the following subfamilies.[2] 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.

(=) Cryptogrammaceae Pic. Serm. 1963
Genera: Coniogramme, Cryptogramma, Llavea
(=) Parkerioideae
(=) Parkeriaceae Hook. 1825
(=) Ceratopteridaceae Underw. 1900
Genera: Acrostichum, Ceratopteris
Genera: Actiniopteris, Anogramma, Aspleniopsis, Austrogramme, Cerosora, Cosentinia, Jamesonia (incl. Eriosorus), Nephopteris, Onychium, Pityrogramma, Pteris (incl. Neurocallis & Platyzoma), Pterozonium, Syngramma, Taenitis
(=) Cheilanthaceae B.K. Nayar 1970
Genera: Adiantopsis, Aleuritopteris, Argyrochosma, Aspidotis, Astrolepis, Bommeria, Calciphilopteris, Cassebeera, Cheilanthes, Cheiloplecton, Doryopteris, Hemionitis, Mildella, Notholaena, Paraceterach, Paragymnopteris, Pellaea, Pentagramma, Trachypteris, Tryonella
(=) Adiantoideae (C.Presl) R.M.Tryon 1986
(=) Adiantaceae Newman 1840
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][10]

Pteridaceae

Cryptogrammoideae





Ceratopteridoideae



Pteridoideae





Cheilanthoideae



Vittarioideae





References

  1. ^ a b "Family: Pteridaceae E. D. M. Kirchn.". Germplasm Resources Information Network. United States Department of Agriculture. 2001-08-14. http://www.ars-grin.gov/cgi-bin/npgs/html/family.pl?1270. Retrieved 2011-11-04.
  2. ^ a b Christenhusz, Maarten J. M.; Zhang, Xian-Chun; Schneider, Harald (18 February 2011). "A linear sequence of extant families and genera of lycophytes and ferns". Phytotaxa 19: 7–54. ISSN 1179-3163. http://www.mapress.com/phytotaxa/content/2011/f/pt00019p054.pdf.
  3. ^ Adianteae Tropicos.org. Missouri Botanical Garden. 14 Jan 2012
  4. ^ a b c d e "Pteridaceae". Integrated Taxonomic Information System. http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=500073. Retrieved 2011-11-04.
  5. ^ a b c d e "GRIN Genera of Pteridaceae". Germplasm Resources Information Network. United States Department of Agriculture. http://www.ars-grin.gov/cgi-bin/npgs/html/gnlist.pl?1270. Retrieved 2011-11-04.
  6. ^ Pterideae Tropicos.org. Missouri Botanical Garden. 14 Jan 2012
  7. ^ Parkerieae Tropicos.org. Missouri Botanical Garden. 14 Jan 2012
  8. ^ Vittarieae Tropicos.org. Missouri Botanical Garden. 14 Jan 2012
  9. ^ Schuettpelz & Pryer (2008) "Fern phylogeny" in Biology and Evolution of Ferns and Lycophytes, ed. Tom A. Ranker and Christopher H. Haufler. Cambridge University Press 2008
  10. ^ Schuettpelz et al. (2007) Eric Schuettpelz, Harald Schneider, Layne Huiet, Michael D. Windham, Kathleen M. Pryer: "A molecular phylogeny of the fern family Pteridaceae: Assessing overall relationships and the affinities of previously unsampled genera." Molecular Phylogenetics and Evolution 44 (2007) 1172–1185
Creative Commons Attribution Share Alike 3.0 (CC BY-SA 3.0)

Source: Wikipedia

Unreviewed

Article rating from 0 people

Average rating: 2.5 of 5

Disclaimer

EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.

To request an improvement, please leave a comment on the page. Thank you!