Conochilus (cone-ow-kile-us), this is a colonial rotifer (metazoa), in which the basal parts of the rotifers are embedded in a common gelatinous matrix. The feeding areas, the coronas, project outwards. Rotifers are common members of the microbial communities of many aquatic ecosystems. Although they are multiceullar animals, they may be only be 100 microns long, and so overlap in size with ciliates. They can be confused with ciliates because they use cilia to capture their food. However, they can be distinguished because they have an exoskeleton, usually two posterior toes, and a tough pharyngeal region just behind the head. Dark ground illumination.