Cryptogam

From Wikipedia, the free encyclopedia
Polystichum setiferum, a fern
Grimmia pulvinata, a moss
Pelvetia canaliculata, a brown alga
Hypholoma fasciculare, a fungus

A cryptogam (scientific name Cryptogamae) is a plant (in the wide sense of the word) that reproduces by spores, without flowers or seeds. "Cryptogamae"(Greek κρυπτός kryptos, "hidden" + γαμέω, gameein, "to marry") means hidden reproduction, referring to the fact that no seed is produced, thus cryptogams represent the non-seed bearing plants. Other names, such as "thallophytes", "lower plants", and "spore plants" are also occasionally used. As a group, Cryptogamae are the opposite of the Phanerogamae (Greek φανερός, phaneros = "visible") or Spermatophyta (Greek σπέρμα, sperma = "seed" and φυτόν, phyton = "plant"), the seed plants. The best known groups of cryptogams are algae, lichens, mosses and ferns.[1] The classification is now deprecated in Linnaean taxonomy.

At one time, the cryptogams were formally recognised as a group within the plant kingdom. In his system for classification of all known plants and animals, Carl Linnaeus (1707–1778) divided the plant kingdom into 24 classes,[2] one of which was the "Cryptogamia". This included all plants with concealed reproductive organs. He divided Cryptogamia into four orders: Algae, Musci (bryophytes), Filices (ferns), and Fungi.

Currently, not all cryptogams are treated as part of the plant kingdom; the fungi, in particular, are regarded as a separate kingdom, more closely related to animals than plants, while blue-green algae are now regarded as allied with the bacteria. Therefore, in contemporary plant systematics, "Cryptogamae" is not a name of a scientifically coherent group, but is cladistically polyphyletic. However, all organisms known as cryptogams belong to the field traditionally studied by botanists and the names of all cryptogams are regulated by the International Code of Nomenclature for algae, fungi, and plants.

See Also

Plant, to see how cryptogams are distributed across modern classification systems

References

  1. ↑ "Cryptogams". Royal Botanic Garden, Edinburgh. Archived from the original on 2007-11-18. Retrieved 2007-07-02. 
  2. ↑ P. S. Dixon (1973). Biology of the Rhodophyta. Oliver and Boyd, Edinburgh. ISBN 0-05-002485-X. 
This article is issued from Wikipedia. The text is available under the Creative Commons Attribution/Share Alike; additional terms may apply for the media files.