Protists within the supergroup Chromalveolates and the group alveolates.
Ciliates are large, varied group of protists named for their use of cilia to move and feed. The cilia may completely cover the cell surface or may be clustered in a few rows or tufts. In certain species, rows of tightly packed cilia function collectively in locomotion. Other ciliates scurry about on leg-like structures constructed from many cilia bonded together.
A distinctive feature of ciliates is the presence of two types of nuclei: tiny micronuclei and large macronuclei. A cell has one or more nuclei of each type.
Genetic variation results from conjugation, a sexual process in which two indivudals exchange haploid micronuclei. Ciliates generally reproduce asexually by binary fission, during which the existing macronucleus disintegrates and a new one is formed from the cell's micronuclei. Each macronucleus typically contains multiple copies of the ciliate's genome.
Genes in the macronucleus control the everyday functions of the cell, such as feeding, waste removal and maintaing water balance.