Morphological and ssrDNA sequence based molecular characterization of a novel Thelohanellus species (Myxosporea: Myxobolidae) infecting the fins of Goldfish, Carassius auratus L. with special reference to its histopathological alteration.

•Description of a new species, Thelohanellus goldi n. sp. on the basis of morphological and morphometrical data along with molecular data.•The severity of infection due to Thelohanellus goldi n. sp. have been assessed by the histopathological changes of fin.•The present paper also deals with the taxonomic description and the prevalence of the myxozoan parasites in goldfish, Carassius auratus in India.