Chytridiomycota

From Wikipedia, the free encyclopedia

Chytridiomycota
Fossil range: Devonian - Recent

Scientific classification
Kingdom: Fungi
Type species
Chytridium spp.
A. Braun, 1851
Classes

Chytridiomycetes
Monoblepharidomycetes

Chytridiomycota is a division of the Fungi kingdom. The name refers to the chytridium (from the Greek chytridion, meaning "little pot"): the structure containing unreleased spores. In older classifications, chytrids (except the recently established order Spizellomycetales) were placed in the Class Phycomycetes under the Subdivision Myxomycophyta of the Kingdom Fungi. However, chytrids are actually protistans. Also, in an older and more restricted sense (not used here), the term "chytrids" referred just to those fungi in the order Chytridiales.

The chytrids are the most primitive of the fungi and are mostly saprobic (degrading chitin and keratin). Many chytrids are aquatic (mostly found in fresh water). There are approximately 1,000 chytrid species, in 127 genera, distributed among 5 orders.

Both zoospores and gametes of the chytrids are mobile by their flagella, one whiplash per individual. The thalli are coenocytic and usually form no true mycelium (having rhizoids instead). Some species are unicellular. Like other fungi, the cell wall in chytrids is composed of chitin.

Some chytrid species are known to kill amphibians in large numbers. The actual process, however, is unknown. The infection is referred to as chytridiomycosis. Decline in frog populations led to the discovery of chytridomycosis in 1998 in Australia and Panama. Chytrids may also infect plant species; in particular, maize-attacking and alfalfa-attacking species have been described. Synchytrium endobioticum is an important potato pathogen.

The earliest fossils of chytrids are from the Scottish Rhynie chert, a Devonian-age locality with anatomical preservation of plants and fungi. Among the microfossils are chytrids preserved as parasites on rhyniophytes. These fossils closely resemble the genus Allomyces.[1]

[edit] References

  1. ^ Taylor, T.N.; W. Remy, & H. Hass. (1994). "Allomyces in the Devonian". Nature 367: 601. doi:10.1038/367601a0. 

[edit] External links

Wikimedia Commons has media related to: