Some more myxosporidia observed in Canadian fishes

Abstract

Seven species of marine fishes and three of fresh or brackish water Canadian fishes have yielded new or known Myxosporidia. The marine fishes were from St Andrews, New Brunswick and Halifax, Nova Scotia, places 250–275 miles apart by sea, and from the Labrador coast. The brackish and freshwater fishes were obtained in Montreal and the Salmon River, Nova Scotia.Descriptions and illustrations are given of the morphology of five new species of Myxosporidia: Ceratomyxa urophysis, Myxoproteus myoxocephali, Myxidium myoxocephali, Myxosoma diaphana and Henneguya amiae.Chloromyxum leydigi Mingazzini, C. granulosum Davis, Myxidium lieberkuhni Bütschli, Myxidium gadi Georgévitch and Zschokkella hildae Auerbach are recorded from new piscine hosts in Canada.Some effects of the Myxosporidian infections, both macroscopic and microscopic, on their hosts are considered. Comparison of the effects of similar infections of Myxosporidia on allied fishes in Normandy and Eastern Canada has shown a general similarity between them.The economic importance of some Myxosporidian infections of the edible fish examined is shown by parasitism of the cod, haddock and sculpin. Amia calva is also used for food in Montreal. The possibility of edible fishes acquiring Myxosporidian infections by way of their food is noted, with reference to the host-specificity of the Myxosporidia of Fundulus heteroclitus described by Bond.The influence of environment on and powers of adaptation to different habitats exhibited by certain Myxosporidia is discussed.Some remarks are made on the zoogeographical distribution of certain Myxosporidia and their piscine hosts.