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At least 235 records · Page 13Linked to original sources
USGS1963

Two new Gyrodactylus (Trematoda: Monogenea) from cyprinid fishes with synopsis of those found on North American fishes

Gyrodactylus atratuli from the blacknose dace ( Rhinichthys atratulus ) and the pearl dace ( Semotilus margarita ) is compared with known species of Gyrodactylus from North American fishes and described as a new species. Gyrodactylus margaritae from the pearl dace ( Semotilus margarita ) is compared with known species of Gyrodactylus from North American fishes and described as a new species. The average number of G. atratuli per blacknose dace in the natural habitat is 7.8 (1 to 32) and in the laboratory at the same water temperature after 55 days in captivity, 5.4 (0 to 11). G. atratuli and G. margaritae fail to live and reproduce on fish kept in nonrunning water at between 19 and 26 C in laboratory aquaria, but will live and reproduce in running spring water at 12 C in laboratory aquaria. An illustrated synopsis with a comparative table of measurements of known North American Gyrodactylus and a list of the species with brief reference to their differentiating characteristics are given.

Journal of Parasitology↗
USGS1963

Studies on Neogogatea kentuckiensis (Cable, 1935) n. comb.: (Trematoda: Strigeoidea: Cyathocotylidae)

The cercaria of N. kentuckiensis was found in Anaplocamus dilatatus ( Nitrocris d. ) and Mudalia carinata . The metacercaria was found in all fishes examined from Opequon River, West Virginia, except Cottus bairdi which was also refractory to experimental infection. Two species of Centrarchidae, four of Cyprinidae, three of Salmonidae, Etheostoma flabellare , Platypoecilus maculatus , and Trichogaster trichopterus were experimentally infected. The development of the metacercaria and cyst and effect on the fish are described. The histopathology initially consists of hemorrhage and muscle necrosis about the metacercaria, followed by reorganization and formation of a loose connective tissue cyst. The controversial adult names are discussed and an emendation of the genus Neogogatea is presented.

Journal of Parasitology↗
USGS1975

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

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 .

Journal of Parasitology↗
USGS1975

Thin-section electron microscopy of mature Myxosoma cerebralis (Myxosporidea) spores

The morphology of purified, mature Myxosoma cerebralis spores was examined by thin-section electron microscopy. Surface architecture corresponded closely to that described in an earlier scanning electron microscopy study of this organism (Lom and Hoffman, 1971). A uniformly thick spore wall is composed of finely granular, electron-lucent material. Intrawall "valvoplasm" at the sutural border region contains small, light spheroidal profiles with dense centers situated in a background matrix; such structures are absent in the intermediate wall areas. Ovoid polar capsules contain complex filamentous profiles within the peripheral matrix region. Individual filaments appear twisted into S-shaped configurations and contain moderately electron-opaque material within their lumina.

Journal of Parasitology↗
USGS1975

Polypodium sp. (Coelenterata) infection of paddlefish (Polyodon spathula) eggs

Parasitism of fish by coelenterates is rare and the first North American infection was reported in sturgeon (Hoffman et al., 1974, J Parasitol 60: 548-550). In the USSR parasitism of sturgeon (Acipenser sp.) eggs by the coelenterate Polypodium hydriforme Ussov 1885 has long been reported and investigated [Raikova, 1959, in Parasites of Freshwater Fish and the Biological Basis for their Control. Bull State Sci Res Inst Lake and River Fish. XLIX. Eng. transl. No. TT61-31056, O. T. S., U. S. Dep. Commerce, Washington, D. C., 1962, 235 p.: Raikova, 1973, (Proc Second Internat Symp on Cnidaria), Seto Marine Biological Laboratory 20: 165-173]. This report represents the first known infection of Polypodium in the paddlefish (Polyodon spathula).

Journal of Parasitology↗