''Ophioglossum'', the adder's-tongue ferns, is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

of about 50 species of

ferns 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 t ...

in the family

Ophioglossaceae Ophioglossaceae, the adder's-tongue family, is a small family of ferns. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), it is the only family in the order Ophioglossales, which together with the Psilotales is placed in the ...

. The name ''Ophioglossum'' comes from the

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

meaning "snake-tongue".eFloras: ''Ophioglossum''
accessed 14 February 2014. Their cosmopolitan distribution is mainly in tropical and subtropical

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

s. The genus has the largest number of

chromosome A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins ar ...

s in the known plant kingdom, but contrary to popular belief does not have the largest number of chromosomes out of all known organisms, falling short to the protist ''

Sterkiella histriomuscorum ''Sterkiella histriomuscorum'', formerly ''Oxytricha trifallax'', is a ciliate species in the genus '' Sterkiella'', known for its highly fragmented genomes which have been used as a model for ciliate genetics. Genetics Like all ciliates, ''O. ...

''.

Description

Adders-tongues are so-called because the

spore In biology, a spore is a unit of sexual or asexual reproduction that may be adapted for dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the life cycles of many plants, algae, ...

-bearing stalk is thought to resemble a snake's tongue. Each plant typically sends up a small, undivided leaf blade with netted venation, and the spore stalk forks from the leaf stalk, terminating in sporangia which are partially concealed within a structure with slit sides. When the leaf blade is present, there is not always a spore stalk present, and the plants do not always send up a leaf, sometimes going for a year to a period of years living only under the soil, nourished by association with soil

fungi A fungus (plural, : fungi or funguses) is any member of the group of Eukaryote, eukaryotic organisms that includes microorganisms such as yeasts and Mold (fungus), molds, as well as the more familiar mushrooms. These organisms are classified ...

. The plant grows from a central, budding, fleshy structure with fleshy, radiating roots.

Taxonomy

''Ophioglossum'' has a high chromosome count in comparison to other species, with 120 or up to 720 chromosomes possible in intervals of 120 due to polyploidy (multiple possible copies of chromosomes). It has almost 1260 number of chromosomes in the meiocyte (spore mother cell) which undergo meiosis, the reduction division to form the spore with only one set of chromosomes getting incorporated into each spore.

Species

, World Ferns listed the following species: *''Goswamia'' **'' Ophioglossum costatum'' **'' Ophioglossum eliminatum'' – status uncertain **'' Ophioglossum gomezianum'' **''

Ophioglossum gujaratensis ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' **''

Ophioglossum hitkishorei ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' **''

Ophioglossum indicum ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' **''

Ophioglossum isanensis ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' **''

Ophioglossum malviae ''Ophioglossum malviae'' is a species of fern in the genus ''Ophioglossum ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns A fern (Polypodiopsida or Polypodiophyta ) is a member of a group of vascular ...

'' **'' Ophioglossum nudicaule'' **''

Ophioglossum raphaelianum ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' **'' Ophioglossum rubellum'' *''Haukia'' **'' Ophioglossum crotalophoroides'' **''

Ophioglossum opacum ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' **'' Ophioglossum tuberosum'' *''Whittieria'' **''

Ophioglossum engelmannii ''Ophioglossum engelmannii'', commonly known as the limestone adder's-tongue, is a species of fern native to the Western Hemisphere. It is widespread and native to the United States, Mexico, and Central America. Its primary natural habitat is dry ...

'' *''Ophioglossum'' s.s. **'' Ophioglossum ammophilum'' – sometimes included in ''O. gomezianum'' **'' Ophioglossum austroasiaticum'' – possibly a synonym of ''O. reticulatum'' **''

Ophioglossum azoricum ''Ophioglossum azoricum'', the small adder's-tongue fern or lesser adder's-tongue fern, is a small fern of the family Ophioglossaceae. Distribution ''Ophioglossum azoricum'' is an Atlantic–Mediterranean species native to islands in the north ...

'' **''

Ophioglossum californicum ''Ophioglossum californicum'', known by the common name California adder's tongue, is an uncommon species of fern in the family Ophioglossaceae. The fern is native to California, and Baja California in Northwestern Mexico. It is found in the San ...

'' **''

Ophioglossum caroticaule ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' **''

Ophioglossum convexum ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' **'' Ophioglossum coriaceum'' **''

Ophioglossum fernandezianum ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' – doubtful species ** ''Ophioglossum'' × ''giovanninii'' **''

Ophioglossum gracile ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' – may be included in ''O. gramineum'' **'' Ophioglossum gracillimum'' **'' Ophioglossum gramineum'' **''

Ophioglossum harrisii ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' **''

Ophioglossum jaykrishnae ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' – provisionally accepted name **'' Ophioglossum kawamurae'' **'' Ophioglossum lancifolium'' **''

Ophioglossum latifolium ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' **''

Ophioglossum lineare ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' – possibly a synonym of ''O. parvifolium'' **''

Ophioglossum louisii ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' **'' Ophioglossum lusitanicum'' **''

Ophioglossum lusoafricanum ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' **''

Ophioglossum melipillense ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' **'' Ophioglossum namegatae'' – probably a synonym of ''O. petiolatum'' **''

Ophioglossum oblongum ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' **''

Ophioglossum parvifolium ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' **''

Ophioglossum parvum ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of Fern, ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek language, Greek meaning "snake-tongue".

'' **''

Ophioglossum petiolatum ''Ophioglossum petiolatum'' is a species of fern in the family Ophioglossaceae. William Jackson Hooker named this species in 1823. The species occurs in parts of Asia, Australia, and North America. Common names According to Encyclopedia o ...

'' ** ''Ophioglossum'' × ''pierinii'' **'' Ophioglossum polyphyllum'' ** ''Ophioglossum'' × ''pseudoazoricum'' **'' Ophioglossum pusillum'' **''

Ophioglossum reticulatum ''Ophioglossum reticulatum'', the netted adder's-tongue, is a species of fern in the family Ophioglossaceae. It has a pantropical/pansubtropical distribution; Latin America, the Caribbean, Sub-Saharan Africa, Madagascar, Yemen, the Indian Subcont ...

'' **''

Ophioglossum sandieae ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' **''

Ophioglossum scariosum ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' **''

Ophioglossum thermale ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' **''

Ophioglossum thomasii ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' **'' Ophioglossum trilokinathii'' **''

Ophioglossum vulgatum ''Ophioglossum vulgatum'', commonly known as adder's-tongue, southern adders-tongue or adders-tongue fern, is a species of fern in the family '' Ophioglossaceae''. The adder’s tongue fern is generally believed to have the largest number of chr ...

'' **''

Ophioglossum yongrenense ''Ophioglossum'', the adder's-tongue ferns, is a genus of about 50 species of ferns in the family Ophioglossaceae. The name ''Ophioglossum'' comes from the Greek meaning "snake-tongue".

'' Species that may be placed in this genus include: *''Ophioglossum bergianum'' = ''

Rhizoglossum bergianum ''Rhizoglossum'' is a genus of fern in the family Ophioglossaceae. Its only species is ''Rhizoglossum bergianum'', native to the Cape Provinces of South Africa. The species was first described, as ''Ophioglossum bergianum'', by Carl Presl in 18 ...

'' *''Ophioglossum falcatum'' = '' Ophioderma falcatum'' *''Ophioglossum intermedium'' = '' Ophioderma intermedium'' *''Ophioglossum simplex'' = '' Ophioderma simplex''

References

External links

Flora of North America: ''Ophioglossum'' (Adder's-tongue)
{{Taxonbar, from=Q781270 Ophioglossaceae Fern genera Taxa named by Carl Linnaeus