Coleps is a genus of ciliates. They are characterized by the presence of a biomineralized test of calcium carbonate, or chalk, in which the cell resides. At one end is a small aperture from which the cell may feed. Coleps are viscous predators, often latching onto their prey and ripping of chunks of tissue or cytoplasm. To make matters worse, Coleps  are often found in swarms. These cells are around 50 micrometers in size.