Genus: Woronchinia and Coelosphaerium
Cyanobacteria (blue green algae)
Woronchinia and Coelosphaerium are cyanobacteria that form a hollow sphere of cells. The colony is only one cell layer thick. Woronchinia and Coelosphaerium look similar to Microcystis, but if you optically dissect the colony, you will see the ring of cells (as shown in the picture). The images attached show the view from the top of the colony and an optically dissected view. A few Coelosphaerium species are synonymous with the Woronchinia genus and other species can be difficult to differentiate. Woronchinia forms a hollow colony but has thick stalks connecting the cells in the center of the colony.