Division cyst with tomites

Description:

Division cyst of Ophryoglena sp. (Ehrenberg, 1831) containing four tomites. Tomites are fission products of the divisional stage of histophagous ciliates, the tomont. The tomont encysts and undergoes rapid divisions into tomites that are small free-swimming non-feeding forms that then become feeding or vegetative forms called trophonts. These, in turn become tomonts. The closely spaced somatic kineties of the tomite at 11 o’clock are evident. The organelle of Lieberkühn is visible in the tomite at 9 o’clock and the one at 2 o’clock in this image. Collected from a freshwater pond near Boise, Idaho. DIC.