Abstract
Ciliated protists (Ciliophora) are diverse (~8,000 formally described species) and ancestral (~1.1 billion years old) organisms, forming a monophyletic group of unicellular eukaryotes capable of colonizing almost any marine and terrestrial ecosystem, acting as top predators of bacteria and other microorganisms. Interestingly, even with this intimate coevolutionary history, there are no re…