Everything Totally Explained


Ask & we'll explain, totally!
Cercozoa
Totally Explained


  NEW! All the latest news in the worlds of computer gaming, entertainment, the environment,  
finance, health, politics, science, stocks & shares, technology and much, much, more.  


View this entry using RSS

Everything about The Cercozoa totally explained

The Cercozoa are a group of protists, including most amoeboids and flagellates that feed by means of filose pseudopods. These may be restricted to part of the cell surface, but there's never a true cytostome or mouth as found in many other protozoa. They show a variety of forms and have proven difficult to define in terms of structural characteristics, although their unity is strongly supported by genetic studies. Cercozoa are closely related to Foraminifera and Radiolaria, amoeboids that usually have complex shells, and together with them form a supergroup called the Rhizaria.
   The best-known Cercozoa are the euglyphids, filose amoebae with shells of siliceous scales or plates, which are commonly found in soils, nutrient-rich waters, and on aquatic plants. Some other filose amoebae produce organic shells, including the tectofilosids and Gromia. They were formerly classified with the euglyphids as the Testaceafilosia. This group isn't monophyletic, but nearly all studied members fall in or near the Cercozoa, related to similarly shelled flagellates.
   Another important group placed here are the chlorarachniophytes, strange amoebae that form a reticulating net. They are set apart by the presence of chloroplasts, which apparently developed from an ingested green alga. They are bound by four membranes and still possess a vestigial nucleus, called a nucleomorph. As such, they've been of great interest to researchers studying the endosymbiotic origins of organelles.
   Other notable cercozoans include the cercomonads, which are common soil flagellates, and the Phaeodarea, marine protozoa that were previously considered radiolarians. In addition, three groups that are traditionally considered heliozoans belong here: the dimorphids, desmothoracids, and gymnosphaerids. The exact composition and classification of the Cercozoa are still being worked out. A general scheme is:
Class Chlorarachnea chlorarachniophytes
Class Proteomyxidea gymnophryids, dimorphids, desmothoracids, gymnosphaerids, etc.
Class Sarcomonadea cercomonads
Class Imbricatea / Silicofilosea euglyphids and thaumatomonads
Class Thecofilosea tectofilosids and cryomonads
Class Phaeodarea
Class Ebridea ebriids
In addition two groups of parasites, the Phytomyxea and Ascetosporea, and the shelled amoeba Gromia may be basal Cercozoa, although some trees place them closer to the Foraminifera. The spongomonads have been included here, but more recently have been considered Amoebozoa. Some other small groups of protozoans are considered Cercozoa but are of uncertain placement, and it's likely many obscure genera will turn out to be cercozoans with further study.

Further Information

Get more info on 'Cercozoa'.


External Link Exchanges

Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:

    <a href="http://cercozoa.totallyexplained.com">Cercozoa Totally Explained</a>

Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
   As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned.



Copyright © 2007-8 totallyexplained.com | Licensed under the GNU Free Documentation License | Site Map
This article contains text from the Wikipedia article Cercozoa (History) and is released under the GFDL | RSS Version