Dipteris


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

Description

Species of Dipteris grow from creeping rhizomes, and have large stalks to the sporangium and annulus. The rhizomes have bristles and the fronds have uniseriate hairs. All species of Dipteris have spore-capsules that are carried on the lower surface of the broad lobed frond. The fronds can reach up to 50 cm long.

Taxonomy

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,. It was then later placed into a separate genus, Bower, Ching and Pichi-Sermolli all having recreated the family Dipteridaceae, then comprising only one genus, Dipteris, due to the differences in sporangium, stomata and gametophyte.
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.

Taxonomy

, Plants of the World Online 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, and some islands in the Pacific Ocean
  • Dipteris lobbiana T. Moore
  • Dipteris nieuwenhuisii Christ
  • Dipteris novoguineensis Posth.
  • Dipteris papilioniformis Kjellb.
  • Dipteris wallichii 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. Most of the species grow on rocks, exposed places, clearings and in thickets.

Fossils

The genus has been found to have been widely distributed during the Jurassic period, of the Mesozoic Era when much of the genus was widely distributed around Europe. Such fossils have been found in England, Germany, France, Belgium, Austria, Switzerland, Bornholm, Greenland, and Poland.