Encyclopedia > Desmothoracid

  Article Content

Desmothoracid

A group of heliozoan protists, usually sessile and found in freshwater environments. The adult is a spherical cell surrounded by a perforated organic lorica, or shell, with many radial pseudopods projecting through the holes to capture food. These are supported by small bundles of microtubules that arise near a point on the nuclear membrane; unlike other heliozoans, the microtubules are not in any regular geometric array, and there does not appear to be a microtubule organizing center to speak of. The mitochondria have tubular cristae, and there is no distinction between the outer and inner cytoplasm.

There are three genera in the group: Clathrulina[?], Hedriocystis[?], and Cienkowskya[?]. Monomastigocystis appears to be a synonym for the last. The cells are usually 10-20 μm in diameter, with an envelope that may be a couple times that size. Reproduction is by the budding off of small motile cells, usually with two flagella. Later these are lost, and pseudopods and a lorica are formed. Typically a single lengthened pseudopod will secrete a hollow stalk that attaches the adult to the substrate.



All Wikipedia text is available under the terms of the GNU Free Documentation License

 
  Search Encyclopedia

Search over one million articles, find something about almost anything!
 
 
  
  Featured Article
Lake Ronkonkoma, New York

... units at an average density of 546.4/km² (1,414.4/mi²). The racial makeup of the town is 93.53% White, 1.36% African American, 0.15% Native American, 2.41% ...

 
 
 
This page was created in 35.5 ms