Heliozoa


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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.

References in periodicals archive ?
Electron microscopic observations on scales of species of the genus Acanthocystis (Centrohelidia, Heliozoa) from Chile, I.
An electron microscopical study of freshwater heliozoa (genus Acanthocystis, Centrohelidia) from Chile, New Zealand, Malaysia and Sri Lanka.
On the centrohelid and rotosphaerid heliozoa from the environs of the Vortsjarv Limnological Station in Estonia.
Morphology of the scales of the freshwater heliozoan Raphidocystis tubifera (Heliozoa, Centrohelida) and organization of the intact scale layer.
Organization and control of microtubule pattern in centrohelidan Heliozoa. J.
The British Freshwater Rhizopoda and Heliozoa. Vol.
Heterotrophic flagellates, centrohelid heliozoa and filose amoebae from marine and freshwater sites in the Antarctic.