Originally the heliozoa were treated together as a formal class Heliozoa or Heliozoea, but the various orders show notable differences and are no longer believed to be related. Instead, heliozoa is regarded as a descriptive term applying to various lines of protists. These include the following:
Several nucleariids were once considered heliozoa, but they do not have microtubule-supported axopods and so are now considered filose amoeboids instead.
Actinosphaerium (single-celled) is an example of a heliozoa. For an image see http://www.microscopy-uk.org.uk/index.html?http://www.microscopy-uk.org.uk/ponddip/