Heliozoa

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The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Heliozoa

 

a subclass of protozoans of the class Sarcodina. The body is usually globose and has raylike appendages (pseudopodia) with dense protoplasmic axial filaments. Heliozoans include naked forms and forms having an external siliceous skeleton. There may be one or more nuclei. The majority of heliozoans are freshwater or marine planktonic organisms; some attach themselves to a substrate by means of a stalk. The protozoans feed on algae, protozoans, and rotifers; several individuals may combine to overcome larger prey. Heliozoans have contractile vacuoles. Reproduction is usually by binary fission. A sexual process has been observed in some species; the gametes resemble small adult individuals.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Morphology of the scales of the freshwater heliozoan Raphidocystis tubifera (Heliozoa, Centrohelida) and organization of the intact scale layer.
On the identity between the heliozoan Pinaciophora fluviatilis and Potamodiscus kalbei with the description of eight new Pinaciophora species.
The heliozoan classification that follows is according to Page and Siemensma (1991).