Celozoic myxosporidians (Myxidium spp. and Chloromyxum spp.) of cyprinids from the river Esla (León, NW Spain). I. Description of the species.

In the examination of 417 Cyprinids, belonging to 7 species, caught in the Esla river from April 1977 to December 1979, the following celozoic myxosporidians were found: Myxidium macrocapsulare Auerbach, 1910 in Leuciscus cephalus cabeda and Chondrostoma polylepis polylepis; Myxidium carinae n. sp. in Barbus barbus bocagei; Chloromyxum complicatum n. sp. in B. barbus bocagei and L. cephalus cabeda; Chloromyxum chondrostomi n. sp. in Ch. polylepis polylepis; and Chloromyxum cyprini Fujita, 1927 in B. barbus bocagei. All of them were found in the gall bladder, except Chl. cyprini that also parasitizes the liver. The myxosporidians are described and drawings and photomicrographs are presented. Data on the prevalence and intensity of their infections are also given.