''Cryptocaryon irritans'' is a species of
ciliate
The ciliates are a group of alveolates characterized by the presence of hair-like organelles called cilia, which are identical in structure to eukaryotic flagella, but are in general shorter and present in much larger numbers, with a differen ...
s that
parasitize
Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has ...
s marine fish, causing marine white spot disease or marine ich (pronounced ''ick'').
It is one of the most common causes of disease in marine
aquaria.
Taxonomy
''Cryptocaryon irritans'' was originally classified as ''Ichthyophthirius marinus'', but it is not closely related to the other species. It belongs to the class
Prostomatea
Prostomatea is a class of ciliates. It includes the genera ''Coleps
''Coleps'' is a genus of ciliates in the class Prostomatea with barrel-shaped bodies surrounded by regularly arranged plates composed of calcium carbonate.
Description ...
, but beyond that its placement is still uncertain.
Clinical
The symptoms and life-cycle are generally similar to those of ''
Ichthyophthirius
''Ichthyophthirius multifiliis'', often termed "Ich", is a parasitic ciliate described by the French parasitologist Fouquet in 1876. Only one species is found in the genus which also gave name to the family. The name literally translates as "the ...
'' in freshwater fish, including white spots, on account of which ''Cryptocaryon'' is usually called marine ich. However, ''Cryptocaryon'' can spend a much longer time encysted. Fish that are infected with Cryptocaryon may have small white spots, nodules, or patches on their skin, fins, or gills. They may also have ragged fins, cloudy eyes, pale gills, increased mucus production, or changes in skin color, and they may appear thin. Behaviorally, fish may act different. They may scratch, swim abnormally, act lethargic, hang at the surface or on the bottom, or breathe more rapidly as if they are in distress.
Useful treatments (but not safe for reef tanks or invertebrates) of ''Cryptocaryon irritans'' are
copper solutions,
formalin
Formaldehyde ( , ) (systematic name methanal) is a naturally occurring organic compound with the formula and structure . The pure compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde (refer to section F ...
solutions and
quinine based drugs (such as
chloroquine
Chloroquine is a medication primarily used to prevent and treat malaria in areas where malaria remains sensitive to its effects. Certain types of malaria, resistant strains, and complicated cases typically require different or additional medi ...
phosphate and
quinine diphosphate).
Infections can be extremely difficult to treat because of the presence of other creatures in the tank, such as corals and other invertebrates, which will not survive standard treatments. Ideally fish with ''Cryptocaryon'' are
quarantined in a hospital tank, where they can be treated with a copper salt or using hyposalinity, 1.009 specific gravity. The display tank needs to be kept clear of fish for 6–9 weeks, the longer the better. This gives time for the encysted
tomonts to release infectious theronts, which die within 24–48 hours when they cannot find a
host.
See also
*
Freshwater ich for the similar disease of freshwater fishes
References
Further reading
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External links
''Cryptocaryon''
Intramacronucleata
Ciliate genera
Fish diseases
Veterinary protozoology
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