Ophioglossaceae
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Chobot
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robot Adding: [[he:אופולוסידים]], [[no:Ormetungebregner]]
{{Taxobox
| name = Ophioglossaceae
| image = Ophioglossum closeup.jpg
| image_width = 240px
| image_caption = ''[[Ophioglossum vulgatum]]''
| regnum = [[Plantae]]
| divisio = [[Pteridophyta]]
| classis = [[Psilotopsida]]
| ordo = [[Ophioglossales]]
| familia = '''Ophioglossaceae'''
| subdivision_ranks = Genera
| subdivision =
''[[Botrychium]]''<br/>
''[[Cheiroglossa]]''<br/>
''[[Helminthostachys]]''<br/>
''[[Mankyua]]''<br/>
''[[Ophioglossum]]''<br/>
}}
'''Ophioglossaceae''' , the Adder's tongue family, is a family of [[fern]]s, currently thought to be most closely related to ''[[Psilotaceae]]'', the two together comprising the class [[Psilotopsida]] as the [[Cladistics|sibling group]] to the rest of the ferns. The number of [[genus |genera]] included in the family varies between different authors' treatments, and most conservatively the family is treated as containing fourgenera, ''[[Ophioglossum]]'', ''[[Botrychium]]'', ''[[Helminthostachys]]'', and ''[[Mankyua]]'' (placed in three separate families in some other treatments). A broad definition of the family and its genera have been taken in several recent treatments (e.g., Wagner 1990, Smith et al. 2006, and in the Flora of North America). A notable exception is the classification of Kato (1987), who advocated the division of ''Botrychium'' into four genera: ''Botrychium'' s.s., ''Sceptridium'', ''Japanobotrychium'', and ''Botrypus''.
These ferns differ from the other ferns in several respects:
* they produce only a single [[leaf]] at a time
* instead of the [[sporangium|leptosporangia]] typical of most ferns they produce eusporangia, which are larger, contain more spores, and have thicker walls
* their [[sporophyll]]s are divided into two distinct parts, the sporophore which produces sporangia and has a greatly reduced and modified blade, and the trophophore, which is very similar to the [[trophophyll]]s in size, color, shape, and so forth
* their [[gametophyte]]s are [[wiktionary:subterranean|subterranean]] and rely on [[fungus|fungi]] for their energy (in other words, they are [[mycoheterotrophe|mycoheterotrophic]]), unlike the [[terrestrial plant |terrestrial]], [[photosynthesis|photosynthetic]] gametophytes found in most ferns.
Members of Ophioglossaceae are usually terrestrial (excepting a few [[epiphyte|epiphytic]] species of ''Ophioglossum'') and occur in both [[temperate]] and [[tropical]] areas. The leaves are usually fleshy, and in temperate areas will often turn brownish or reddish during colder months. In addition to having mycoheterotrophic gametophytes, there are a few members of ''Botrychium'' that are unique among ferns in having the [[sporophyte]]s also mycoheterotrophic, producing only small, ephemeral sporophylls that do not photosynthesize.
The genera ''[[Botrychium]]'' (with its segregate genera ''[[Botrypus]]'', ''[[Japanobotrychium]]'' and ''[[Sceptridium]]'') and ''[[Helminthostachys]]'' are sometimes placed in their own families, [[Botrychiaceae]] and [[Helminthostachyaceae]], respectively.
==References and external links==
*Kato, M. 1987. A phylogenetic classification of Ophioglossaceae. ''Gardens Bulletin (Singapore)'' 40: 1-14.
*Smith, A. R., K. M. Pryer, E. Schuettpelz, P. Korall, H. Schneider & P. G. Wolf. 2006. A classification for extant ferns. ''Taxon'' 55(3):705–731.
*Wagner, W. H. 1990. Ophioglossaceae, Pp. 193-197 in K. Kubitzki (ed.), ''The families and genera of vascular plants. Volume 1. Pteridophytes and gymnosperms.'' K. U. Kramer and P. S. Green, volume eds. Springer-Verlag, Berlin.
*[http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=10634 Ophioglossaceae in Flora of North America] (incl. Botrychiaceae)
{{commonscat}}
[[Category:Ophioglossales]]
[[Category:Plant families]]
[[da:Slangetunge-familien]]
[[de:Natternzungengewächse]]
[[es:Ophioglossaceae]]
[[fr:Ophioglossaceae]]
[[ko:나도고사리삼문]]
[[he:אופולוסידים]]
[[lt:Driežlieliniai]]
[[no:Ormetungebregner]]