Species name： Actinosphaerium sp.
Graduate School of Life Science, University of Hyogo Taniguchi Atsushi
This is Actinosphaerium sp. which multinuclear and large in size. Actinosphaerium is omnivorous and sometime prey large organisms such as rotifer and Stentor. They are usually about 200 µm in size, but as the growing environment becomes worse, they fuse each other and become larger than 1 mm in size. By the way, the particles look brilliant in this video are crystals included in the cell.
(2014.03.29)