Epistylis ciliate. Light microscope footage of a single Epistylis sp. ciliate feeding. Epistylis is a genus of sessile (sedentary) single-celled protozoans, with a long stalk and a flattened head. At the top of the head is the mouth, surrounded by many fine cilia hairs. These create a vortex in the surrounding water, washing food particles into the mouth. Filmed with differential interference contrast illumination.