Cilliates

Also known as: Ciliate protozoans, ciliated protozoa

Ciliates are common single-celled organisms with rows of beating hairs (cilia) and are recognizable under a microscope by their swirling or darting movement. They include both free-living and parasitic species, many of which infect fish in freshwater and marine environments. When present in high numbers, parasitic ciliates can cause serious gill and skin damage.

Distribution: Widespread in aquatic systems

Hosts: Freshwater and marine fish

Detection Methods: Microscopic exam – histology

Target tissue: Gills, skin, fins

Species: Ambiphrya, Apiosoma, Chilodonella, Epistylis, Ichthyophthirius multifiliis (Ich), Trichodina, Trichodinella, Trichophrya