Helizoa with a peculiar structure
A helizoa-like organism is moving slowly, extending many stiff projections called axopods. Several particles are attached to the axopods, so the whole structure looks more complex than usual Helizoas.
Commentary by Prof. Yuji Tsukii, Hosei University
This organism is Raphidiophrys which belongs to the larger group Heliozoea.
The organisms in this group are characterized by spicules on the cell surface. Spicules are also attached to the base of Axopodia.
A number of green algal cells of similar size are seen inside, which may be captured food or symbiotic green algae.
In the Heliozoa group, there is a similar genus Sphaerastrum, but the organism in this video is most likely Raphidiophrys.
Sampling Date : 03 July 2009
Sampling Site : Hirose River B Google Map