Morphological and molecular characterization of acanthocephala infecting commercially available fishes in north India

Abstract

Acanthocephalans are pseudocoelomate obligatory endoparasites of all vertebrate classes. Morpho-molecular characterization of 10 species of the phylum Acanthocephala from the freshwater fishes of North India was conducted, which included 4 and 6 species from the genera Acanthogyrus and Pallisentis, respectively. Of these, A. bispinosa, A. garciai, P. himachalensis, P. longus and P. roparensis infecting Cirrhinus mrigala, Labeo calbasu, Channa punctata, C. marulius and Wallago attu, respectively, are new to science. The overall prevalence of acanthocephalan infection in freshwater fish was 24.69%. All the described species have been supplemented with molecular data based on the 18S, 28S and ITS1-5.8S-ITS2 rRNA molecular markers. The Bayesian inference trees generated in this study showed the distinctive identities of all species, with a significant genetic divergence. The molecular data revealed the monophyletic origin of the genera Acanthogyrus and Pallisentis. The histopathological alterations in the intestine of C. striata, L. rohita and W. attu infected with the acanthocephalan parasites showed no significant changes except epidermal desquamation, hyperplasia, mucosal damage, dilation of the lymphatic vessels and an inflammatory immune response. newline