Abstract
Isoparorchis is an endoparasite of fish that is found in the swim bladder of Wallago attu. Isoparorchis is predominant in Asian countries, Russia and also Australia. Four species of Isoparorchis have been found to be taxonomically valid. In India, I. hypselobagri and I. trisimilibutis have been morphologically described. The sample collected from Northeast India is subjected to both morphological and molecular analysis. Molecular markers like mitochondrial Cytochrome Oxidase I gene and the ribosomal Internal Transcribed Spacer 2 gene markers have aided the identification and characterization of parasites particularly flatworms. The morphological and the molecular assessment indicate the presence of I. trisimilibutis in Northeast India. This report is the first locality and regional report from India.