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A disease of freshwater fishes caused by Tetrahymena corlissi Thompson, 1955, and a key for identification of holotrich ciliates of freshwater fishes

G. L. Hoffman·M. Landolt·J.E. Camper·D.W. Coats·J.L. Stookey·J.D. Burek
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Abstract

Tetrahymena corlissi , a free-living protozoan, apparently caused the death of large numbers of guppies ( Poecilia reticulatus ) and occasionally other fishes, in aquaria and hatcheries at several locations. Apparently the disease occurs when the fish and protozoan populations are both at a high level of density. The signs include white spots and epidermal damage. Histologically, T. corlissi could be seen in skin, muscle, and viscera; in some there was marked inflammation, in others there was little tissue reaction. A key is presented for the identification of invasive fish ciliates: Chilodonella , Hemiophrys , Ichthyophthirius , Ophryoglena , and Tetrahymena .

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G. L. Hoffman, M. Landolt, J.E. Camper, D.W. Coats, J.L. Stookey, J.D. Burek. 1975. A disease of freshwater fishes caused by Tetrahymena corlissi Thompson, 1955, and a key for identification of holotrich ciliates of freshwater fishes. https://doi.org/10.2307/3278995

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