''Dipteris'' is a genus of about seven species of ferns, native to tropical regions across the world, particularly Asia, with a species in northeastern Queensland in

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

. It is one of two genera in the family Dipteridaceae.

Description

Species of ''Dipteris'' grow from creeping

rhizomes In botany and dendrology, a rhizome (; , ) is a modified subterranean plant stem that sends out roots and shoots from its nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow hori ...

, and have large stalks to the sporangium and

annulus Annulus (or anulus) or annular indicates a ring- or donut-shaped area or structure. It may refer to: Human anatomy * ''Anulus fibrosus disci intervertebralis'', spinal structure * Annulus of Zinn, a.k.a. annular tendon or ''anulus tendineus com ...

. The rhizomes have bristles (or hairs) and the fronds have uniseriate hairs (having one line or series). All species of ''Dipteris'' have spore-capsules that are carried on the lower surface of the broad lobed frond.A. C. Seward The fronds can reach up to 50 cm long.

Taxonomy

Caspar Georg Carl Reinwardt first published the genus in 1825, by describing ''Dipteris conjugata'' Reinw. which is the best known species. In 1839, R. Brown reduced the genus to a subgenus of '' Polypodium''. In 1901, Konrad Christ published ''Die Farnkrauter der Erde't'', within which he included the genus ''Dipteris'' in the family Polypodiaceae, (a subdivision of the Polypodiacea). It was then later placed into a separate genus,A. C. Seward Bower (1928), Ching (1940) and Pichi-Sermolli (1958) all having recreated the family Dipteridaceae, then comprising only one genus, ''Dipteris'', due to the differences in

sporangium A sporangium (; from Late Latin, ) is an enclosure in which spores are formed. It can be composed of a single cell or can be multicellular. Virtually all plants, fungi, and many other lineages form sporangia at some point in their life cy ...

stomata In botany, a stoma (from Greek ''στόμα'', "mouth", plural "stomata"), also called a stomate (plural "stomates"), is a pore found in the epidermis of leaves, stems, and other organs, that controls the rate of gas exchange. The pore is bor ...

and gametophte.Peter H. Hovenkamp The Latin genus name ''Dipteris'' refers to an amalgamation of two terms: ''di'' meaning two, and ''pteris'' Greek word used for ferns generally, meaning wing-like.

Species

, ''

Plants of the World Online Plants of the World Online (POWO) is an online database published by the Royal Botanic Gardens, Kew. It was launched in March 2017 with the ultimate aim being "to enable users to access information on all the world's known seed-bearing plants by ...

'' and the ''Checklist of Ferns and Lycophytes of the World'' recognized seven species: *'' Dipteris chinensis '' Christ – Tropical Asia and Australasia *'' Dipteris conjugata'' Reinw. – Indochina to Australia (Queensland), and some islands in the Pacific Ocean *'' Dipteris lobbiana'' (Hook.) T. Moore – Cuba, Hispaniola *'' Dipteris nieuwenhuisii'' Christ *'' Dipteris novoguineensis'' Posth. *'' Dipteris papilioniformis'' Kjellb. *'' Dipteris wallichii '' (R. Br.) T. Moore – India, Cuba, Hispaniola ''Dipteris polyphyllus'', a species from New Guinea has not been fully accepted as a species.

Distribution and habitat

Many species are found in Malaysia, Philippines, Samoa and New Guinea, growing beside ''

Matonia ''Matonia'' is a genus of fern, named for English botanist William George Maton. It is native to Thailand, Malesia (the Malayan peninsula, Borneo, Sumatra, Maluku and the Philippines) and New Guinea. , ''Plants of the World Online'' and the ''Ch ...

'' (another fern species). Most of the species grow on rocks, exposed places, clearings and in thickets.K.U. Kramer, Klaus Kubitzki, P.S. Green (Editors)

Fossils

The genus has been found to have been widely distributed during the Jurassic period,R.D. Preton and H.W. Woolhouse of the

Mesozoic Era The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last Era (geology), era of Earth's Geologic time scale, geological history, lasting from about , comprising ...

when much of the genus was widely distributed around Europe. Such fossils have been found in England, Germany, France, Belgium, Austria,

Switzerland ). Swiss law does not designate a ''capital'' as such, but the federal parliament and government are installed in Bern, while other federal institutions, such as the federal courts, are in other cities (Bellinzona, Lausanne, Luzern, Neuchâtel ...

Bornholm Bornholm () is a Danish island in the Baltic Sea, to the east of the rest of Denmark, south of Sweden, northeast of Germany and north of Poland. Strategically located, Bornholm has been fought over for centuries. It has usually been ruled by ...

(island), Greenland, and Poland.

References

Other sources

* Douglas Houghton Campbell, The Evolution of the Land Plants (Embryophyta), 1940 * Anil Kumar, Botany for Degree Pteridophyta, 2006 * Sir Arthur George Tansley, The New Phytologist, 1956

External links

* http://www.efloras.org/florataxon.aspx?flora_id=3&taxon_id=110503 Flora of China {{Taxonbar, from=Q2103553 Gleicheniales Fern genera