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Schizaeales
Schizaeales is an order of ferns (class Polypodiopsida). Description While the three clades of Schizaeales are all well-distinguished from one another by numerous morphological characters, members of the order all have dimorphic fertile and sterile fronds and lack well-defined sori. Their sporangia have a horizontal annulus that lies below and completely encircles the top of the sporangium. Classification In the molecular phylogenetic classification of Smith et al. in 2006, the Schizaeales were placed in the leptosporangiate ferns, class Polypodiopsida. Three families, Anemiaceae, Lygodiaceae, and Schizaeaceae were recognized. The linear sequence of Christenhusz et al. (2011), intended for compatibility with the classification of Chase and Reveal (2009) which placed all land plants in Equisetopsida, reclassified Smith's Polypodiopsida as subclass Polypodiidae and placed the Schizaeales there, with the same three families. The classification of Christenhusz and Chase (2014) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schizaeales
Schizaeales is an order of ferns (class Polypodiopsida). Description While the three clades of Schizaeales are all well-distinguished from one another by numerous morphological characters, members of the order all have dimorphic fertile and sterile fronds and lack well-defined sori. Their sporangia have a horizontal annulus that lies below and completely encircles the top of the sporangium. Classification In the molecular phylogenetic classification of Smith et al. in 2006, the Schizaeales were placed in the leptosporangiate ferns, class Polypodiopsida. Three families, Anemiaceae, Lygodiaceae, and Schizaeaceae were recognized. The linear sequence of Christenhusz et al. (2011), intended for compatibility with the classification of Chase and Reveal (2009) which placed all land plants in Equisetopsida, reclassified Smith's Polypodiopsida as subclass Polypodiidae and placed the Schizaeales there, with the same three families. The classification of Christenhusz and Chase (2014) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leptosporangiate Ferns
The Polypodiidae, commonly called leptosporangiate ferns, formerly Leptosporangiatae, are one of four subclasses of ferns, and the largest of these, being the largest group of living ferns, including some 11,000 species worldwide. The group has also been treated as the class Pteridopsida or Polypodiopsida, although other classifications assign them a different rank. Older names for the group include Filicidae and Filicales, although at least the "water ferns" (now the Salviniales) were then treated separately. The leptosporangiate ferns are one of the four major groups of ferns, with the other three being the eusporangiate ferns comprising the marattioid ferns (Marattiidae, Marattiaceae), the horsetails (Equisetiidae, Equisetaceae), and whisk ferns and moonworts. There are approximately 8465 species of living leptosporangiate ferns, compared with about 2070 for all other ferns, totalling 10535 species of ferns. Almost a third of leptosporangiate fern species are epiphytes. These ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polypodiidae (plant)
The Polypodiidae, commonly called leptosporangiate ferns, formerly Leptosporangiatae, are one of four subclasses of ferns, and the largest of these, being the largest group of living ferns, including some 11,000 species worldwide. The group has also been treated as the class Pteridopsida or Polypodiopsida, although other classifications assign them a different rank. Older names for the group include Filicidae and Filicales, although at least the "water ferns" (now the Salviniales) were then treated separately. The leptosporangiate ferns are one of the four major groups of ferns, with the other three being the eusporangiate ferns comprising the marattioid ferns (Marattiidae, Marattiaceae), the horsetails (Equisetiidae, Equisetaceae), and whisk ferns and moonworts. There are approximately 8465 species of living leptosporangiate ferns, compared with about 2070 for all other ferns, totalling 10535 species of ferns. Almost a third of leptosporangiate fern species are epiphytes. These ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polypodiopsida
A fern (Polypodiopsida or Polypodiophyta ) is a member of a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. The polypodiophytes include all living pteridophytes except the lycopods, and differ from mosses and other bryophytes by being vascular, i.e., having specialized tissues that conduct water and nutrients and in having life cycles in which the branched sporophyte is the dominant phase. Ferns have complex leaves called megaphylls, that are more complex than the microphylls of clubmosses. Most ferns are leptosporangiate ferns. They produce coiled fiddleheads that uncoil and expand into fronds. The group includes about 10,560 known extant species. Ferns are defined here in the broad sense, being all of the Polypodiopsida, comprising both the leptosporangiate (Polypodiidae) and eusporangiate ferns, the latter group including horsetails, whisk ferns, marattioid ferns, and ophioglossoid ferns. Ferns first ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schizaeaceae
Schizaeaceae is a family of ferns in the order Schizaeales. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), it includes only two genera. Alternatively, two families kept separate in PPG I, Lygodiaceae and Anemiaceae, may be included in Schizaeaceae (as the subfamilies Lygodioideae and Anemioideae) so that the family has four genera. In this approach, the Schizaeaceae of PPG I is treated as the subfamily Schizaeoideae. Species are mainly distributed in the tropics, but several are found in temperate regions in North America, South Africa, Australasia and Northeast Asia. The sporangia are borne on specialised pinnae, distinct from ordinary vegetative pinnae. The pinnae form small comb-like, pinnate structures on which the sporangia are formed. Genera In the narrow circumscription of the family, there are two genera: *'' Actinostachys'' Wall *'' Schizaea'' Sm. Two further genera are included in the broader circumscription: *''Anemia'' Sm. – otherwise placed i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fern
A fern (Polypodiopsida or Polypodiophyta ) is a member of a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. The polypodiophytes include all living pteridophytes except the lycopods, and differ from mosses and other bryophytes by being vascular, i.e., having specialized tissues that conduct water and nutrients and in having life cycles in which the branched sporophyte is the dominant phase. Ferns have complex leaves called megaphylls, that are more complex than the microphylls of clubmosses. Most ferns are leptosporangiate ferns. They produce coiled fiddleheads that uncoil and expand into fronds. The group includes about 10,560 known extant species. Ferns are defined here in the broad sense, being all of the Polypodiopsida, comprising both the leptosporangiate (Polypodiidae) and eusporangiate ferns, the latter group including horsetails, whisk ferns, marattioid ferns, and ophioglossoid ferns. Ferns first ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anemia (plant)
''Anemia'' is a genus of ferns. It is the only genus in the family Anemiaceae in the Pteridophyte Phylogeny Group classification of 2016 (PPG I). Alternatively, the genus may be placed as the only genus in the subfamily Anemioideae of a more broadly defined family Schizaeaceae, the family placement used in ''Plants of the World Online'' . Its species are sometimes called flowering ferns, but this term is more commonly applied to ferns of the genus ''Osmunda''. Fronds are dimorphic; in fertile fronds, the two lowermost pinnae are highly modified to bear the sporangia. Ferns in this genus have chromosome numbers based on ''x''=38: ''n''=38, 76, 114. Taxonomy The genus ''Anemia'' was first described by the Swedish botanist Olof Swartz in 1806. The family Anemiaceae was created by Johann Link in 1841. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), ''Anemia'' includes ''Mohria'' and ''Colina'' and is the only genus in the family. Some sources do not separate the f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Actinostachys
''Actinostachys'' is a genus of small ferns originally included in the genus ''Schizaea''. The genus was segregated on the basis of the flabelliform (fan-shaped) laminae. The genus is colloquially called the ray ferns. Species , World Ferns accepted the following species: *'' Actinostachys balansae'' ( Fourn.) C.F. Reed *'' Actinostachys confusa'' (Selling) C.F. Reed *'' Actinostachys digitata'' ( L.) Wallich ex C.F. Reed *'' Actinostachys inopinata'' (Selling) C.F. Reed *'' Actinostachys intermedia'' (Mett.) C.F. Reed *'' Actinostachys laevigata'' (Mett.) C.F. Reed *'' Actinostachys macrofunda'' Bierh. *'' Actinostachys melanesica'' (Selling) C.F. Reed *'' Actinostachys minuta'' Amoroso & Coritico *'' Actinostachys oligostachys'' Bierh. *'' Actinostachys pennula'' ( Sw.) Hook. *'' Actinostachys plana'' ( Fourn.) C.F. Reed *'' Actinostachys simplex'' Amoroso & Coritico *'' Actinostachys spirophylla'' ( W. Troll) C.F. Reed *'' Actinostachys subtrijuga'' ( Mart.) C. Pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schizaea
''Schizaea'' is a small genus of specialized ferns in the family Schizaeaceae. Common names include curlygrass fern and comb fern. Some species are very small and inconspicuous, and so may often be overlooked in nature. The genus is distinctive and not at all like the common conception of a fern, though it is still considered a true fern (leptosporangiate). The sterile fronds (trophophylls) are grass-like, and the spore-bearing fertile frond (sporophyll) is similar, but with a small, pinnate fertile segment at its apex. The upper surface of the pinnules bear the sessile capsules. Various of the roughly two dozen species have been reported from widely separated regions, including much of the tropical Old and New World, parts of the Eastern USA, Chile, the Falkland Islands, and various Pacific islands, including several islands of New Caledonia, as well as Australia and New Zealand.Brian Swale, Michael Hassler. Family Schizaeaceae, genus Schizaea. http://homepages.caverock.net.nz/ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anemiaceae
''Anemia'' is a genus of ferns. It is the only genus in the family Anemiaceae in the Pteridophyte Phylogeny Group classification of 2016 (PPG I). Alternatively, the genus may be placed as the only genus in the subfamily Anemioideae of a more broadly defined family Schizaeaceae, the family placement used in ''Plants of the World Online'' . Its species are sometimes called flowering ferns, but this term is more commonly applied to ferns of the genus ''Osmunda''. Fronds are dimorphic; in fertile fronds, the two lowermost pinnae are highly modified to bear the sporangia. Ferns in this genus have chromosome numbers based on ''x''=38: ''n''=38, 76, 114. Taxonomy The genus ''Anemia'' was first described by the Swedish botanist Olof Swartz in 1806. The family Anemiaceae was created by Johann Link in 1841. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), ''Anemia'' includes ''Mohria'' and ''Colina'' and is the only genus in the family. Some sources do not separate the f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frond Dimorphism
Frond dimorphism refers to a difference in ferns between the fertile and sterile fronds. Since ferns, unlike flowering plants, bear spores on the leaf blade itself, this may affect the form of the frond itself. In some species of ferns, there is virtually no difference between the fertile and sterile fronds, such as in the genus ''Dryopteris'', other than the mere presence of the sori, or fruit-dots, on the back of the fronds. Some other species, such as ''Polystichum acrostichoides'' (Christmas fern), or some ferns of the genus ''Osmunda'', feature dimorphism on a portion of the frond only. Others, such as some species of ''Blechnum'' and ''Woodwardia'', have fertile fronds that are markedly taller than the sterile. Still others, such as ''Osmunda cinnamomea'' (Cinnamon fern), or plants of the family Onocleaceae, have fertile fronds that are completely different from the sterile. Only members of the ''Onocleaceae'' and ''Blechnaceae'' exhibit a propensity towards dimorphy, while ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Annulus (botany)
{{Short description, A ring of specialized cells on the sporangium An annulus in botany is an arc or a ring of specialized cells on the sporangium. These cells are arranged in a single row, and are associated with the release or dispersal of spores. Ferns In leptosporangiate ferns, the annulus located on the outer rim of the sporangium and serves in spore dispersal. It consists typically of a ring or belt of dead water-filled cells with differentially thickened cell walls that stretches about two-thirds around each sporangium in leptosporangiate ferns. The thinner walls on the outside allow water to evaporate quickly under dry conditions. This dehiscence causes the cells to shrink and a contraction and straightening of the annulus ring, eventually rupturing the sporangial wall by ripping apart thin-walled lip cells on the opposite side of the sporangium. As more water evaporates, air bubbles form in the cells causing the contracted annulus to snap forward again, thus dislodging an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
