The order Salviniales (formerly known as the Hydropteridales and including the former Marsileales) is an order of ferns in the class Polypodiopsida.[1]
Salviniales are all aquatic and differ from all other ferns in being heterosporous, meaning that they produce two different types of spore (megaspores and microspores) that develop into two different types of gametophyte (female and male gametophytes, respectively), and in that their gametophytes are endosporic, meaning that they never grow outside the spore wall and cannot become larger than the spores that produced them. The megasporangia each produce a single megaspore.[1] In being heterosporus with endosporic gametophytes they are more similar to seed plants than to other ferns.
The fertile and sterile leaves are dimorphic, taking on a different shape, and leaves bear anastomosing veins. Aerenchyma is frequently present in roots, shoots, and petioles (leaf stalks).[1]
The ferns of this order vary radically in form and do not look particularly fern-like. Species of the family Salviniaceae are natant (floating), while those of the family Marsileaceae are rooted. However, the natant species may temporarily grow on wet mud during times of low water, and the Marsileaceae may grow as emergent species, depending on species and location.
The group has also the smallest known genomes of all ferns. One genus, Azolla, is amongst the fastest growing plants on earth and caused a cooling of the climate in the Azolla event about 50 million years ago.[2]
There is a well-known fossil member of the Marsileales, Hydropteris (incertae sedis).
ClassificationEdit
In the molecular phylogenetic classification of Smith et al. (2006), the Salviniales were placed in the leptosporangiate ferns, class Polypodiopsida. Two families, Marsileaceae and Salviniaceae, were recognized.[1] The linear sequence of Christenhusz et al. (2011), intended for compatibility with the classification of Chase and Reveal (2009)[3] which placed all land plants in Equisetopsida,[4] reclassified Smith's Polypodiopsida as subclass Polypodiidae and placed the Salviniales there. The circumscription of the order and its families was not changed,[3] and that circumscription and placement in Polypodiidae has subsequently been followed in the classifications of Christenhusz and Chase (2014)[5] and PPG I (2016).[6]
The likely phylogenic relationships between the two families and five genera of the Salviniales are shown in the following diagram.[7][8]
^ abcdSmith, Alan R.; Pryer, Kathleen M.; Schuettpelz, Eric; Korall, Petra; Schneider, Harald; Wolf, Paul G. (August 2006). "A classification for extant ferns" (PDF). Taxon. 55 (3): 705–731. doi:10.2307/25065646. JSTOR 25065646.
^Li, Fay-Wei; et al. (2018). "Fern genomes elucidate land plant evolution and cyanobacterial symbioses". Nature Plants. 4 (7): 460–472. doi:10.1038/s41477-018-0188-8. PMC6786969. PMID 29967517.
^ abChristenhusz, Maarten J. M.; Zhang, Xian-Chun; Schneider, Harald (18 February 2011). "A linear sequence of extant families and genera of lycophytes and ferns" (PDF). Phytotaxa. 19: 7–54. doi:10.11646/phytotaxa.19.1.2. hdl:10138/28042.
^Chase, Mark W.; Reveal, James L. (October 2009). "A phylogenetic classification of the land plants to accompany APG III". Botanical Journal of the Linnean Society. 161 (2): 122. doi:10.1111/j.1095-8339.2009.01002.x.
^Christenhusz, Maarten J. M.; Chase, Mark W. (13 February 2014). "Trends and concepts in fern classification". Annals of Botany. 113 (4): 571–594. doi:10.1093/aob/mct299. PMC3936591. PMID 24532607.
^The Pteridophyte Phylogeny Group (November 2016). "A community-derived classification for extant lycophytes and ferns". Journal of Systematics and Evolution. 54 (6): 563–603. doi:10.1111/jse.12229. S2CID 39980610.
^Nathalie S. Nagalingum, Michael D. Nowak & Kathleen M. Pryer (2008). "Assessing phylogenetic relationships in extant heterosporous ferns (Salviniales), with a focus on Pilularia and Salvinia" (PDF). Botanical Journal of the Linnean Society. 157 (4): 673–685. doi:10.1111/j.1095-8339.2008.00806.x.
^Maarten J. M. Christenhusz, Xian-Chun Zhang & Harald Schneider (2011). "A linear sequence of extant families and genera of lycophytes and ferns" (PDF). Phytotaxa. 19: 7–54. doi:10.11646/phytotaxa.19.1.2. hdl:10138/28042.
C. Michael Hogan. 2010. Fern. Encyclopedia of Earth. National council for Science and the Environment. Washington, DC
October 20, 2023
salviniales, order, formerly, known, hydropteridales, including, former, marsileales, order, ferns, class, polypodiopsida, water, fernsmarsilea, villosascientific, classificationkingdom, plantaeclade, tracheophytesdivision, polypodiophytaclass, polypodiopsidas. The order Salviniales formerly known as the Hydropteridales and including the former Marsileales is an order of ferns in the class Polypodiopsida 1 Salviniales the water fernsMarsilea villosaScientific classificationKingdom PlantaeClade TracheophytesDivision PolypodiophytaClass PolypodiopsidaSubclass PolypodiidaeOrder SalvinialesLinkFamiliesMarsileaceae Mirb in Lam amp Mirb 1802 Salviniaceae Martinov 1820Synonyms Hydropteridales Marsileales Bartl in Mart 1835 Pilulariales Bercht amp J Presl 1820Description EditSalviniales are all aquatic and differ from all other ferns in being heterosporous meaning that they produce two different types of spore megaspores and microspores that develop into two different types of gametophyte female and male gametophytes respectively and in that their gametophytes are endosporic meaning that they never grow outside the spore wall and cannot become larger than the spores that produced them The megasporangia each produce a single megaspore 1 In being heterosporus with endosporic gametophytes they are more similar to seed plants than to other ferns The fertile and sterile leaves are dimorphic taking on a different shape and leaves bear anastomosing veins Aerenchyma is frequently present in roots shoots and petioles leaf stalks 1 The ferns of this order vary radically in form and do not look particularly fern like Species of the family Salviniaceae are natant floating while those of the family Marsileaceae are rooted However the natant species may temporarily grow on wet mud during times of low water and the Marsileaceae may grow as emergent species depending on species and location The group has also the smallest known genomes of all ferns One genus Azolla is amongst the fastest growing plants on earth and caused a cooling of the climate in the Azolla event about 50 million years ago 2 There is a well known fossil member of the Marsileales Hydropteris incertae sedis Classification EditIn the molecular phylogenetic classification of Smith et al 2006 the Salviniales were placed in the leptosporangiate ferns class Polypodiopsida Two families Marsileaceae and Salviniaceae were recognized 1 The linear sequence of Christenhusz et al 2011 intended for compatibility with the classification of Chase and Reveal 2009 3 which placed all land plants in Equisetopsida 4 reclassified Smith s Polypodiopsida as subclass Polypodiidae and placed the Salviniales there The circumscription of the order and its families was not changed 3 and that circumscription and placement in Polypodiidae has subsequently been followed in the classifications of Christenhusz and Chase 2014 5 and PPG I 2016 6 The likely phylogenic relationships between the two families and five genera of the Salviniales are shown in the following diagram 7 8 Salviniales Marsileaceae MarsileaPilulariaRegnellidiumSalviniaceae AzollaSalviniaReferences Edit a b c d Smith Alan R Pryer Kathleen M Schuettpelz Eric Korall Petra Schneider Harald Wolf Paul G August 2006 A classification for extant ferns PDF Taxon 55 3 705 731 doi 10 2307 25065646 JSTOR 25065646 Li Fay Wei et al 2018 Fern genomes elucidate land plant evolution and cyanobacterial symbioses Nature Plants 4 7 460 472 doi 10 1038 s41477 018 0188 8 PMC 6786969 PMID 29967517 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 PDF Phytotaxa 19 7 54 doi 10 11646 phytotaxa 19 1 2 hdl 10138 28042 Chase Mark W Reveal James L October 2009 A phylogenetic classification of the land plants to accompany APG III Botanical Journal of the Linnean Society 161 2 122 doi 10 1111 j 1095 8339 2009 01002 x Christenhusz Maarten J M Chase Mark W 13 February 2014 Trends and concepts in fern classification Annals of Botany 113 4 571 594 doi 10 1093 aob mct299 PMC 3936591 PMID 24532607 The Pteridophyte Phylogeny Group November 2016 A community derived classification for extant lycophytes and ferns Journal of Systematics and Evolution 54 6 563 603 doi 10 1111 jse 12229 S2CID 39980610 Nathalie S Nagalingum Michael D Nowak amp Kathleen M Pryer 2008 Assessing phylogenetic relationships in extant heterosporous ferns Salviniales with a focus on Pilularia and Salvinia PDF Botanical Journal of the Linnean Society 157 4 673 685 doi 10 1111 j 1095 8339 2008 00806 x Maarten J M Christenhusz Xian Chun Zhang amp Harald Schneider 2011 A linear sequence of extant families and genera of lycophytes and ferns PDF Phytotaxa 19 7 54 doi 10 11646 phytotaxa 19 1 2 hdl 10138 28042 C Michael Hogan 2010 Fern Encyclopedia of Earth National council for Science and the Environment Washington DC Retrieved from https en wikipedia org w index php title Salviniales amp oldid 1180288373, wikipedia, wiki, book, books, library,
