portrait

Description:

Cyclidium (sigh-clid-ee-um) a common and widespread filter-feeding ciliate. This is a scuticociliate in which one of the aggregates of cilia associated with the mouth forms a veil to one side (here to the left) and this is used to help separate particles of food- bacteria - from the water. Phase contrast. Material from Nymph Creek and Nymph Lake, thermal sites within Yellowstone National Park, photograph by Kathy Sheehan and David Patterson.