Histopathology of Anilocra leptosoma Bleeker, 1857 (Isopoda, Cymothoidae) Infestation on Its New Host Nematalosa nasus (Bloch, 1795) From India

Cymothoid isopods are parasitic crustaceans that cause serious impact on marine fish and might lead to fish mortality and consequently, economic losses. Histopathological alterations caused by Anilocra spp. have not been studied well. This study aims to report the histopathological changes caused by Cymothoid, Anilocra leptosoma Bleeker, 1857 in the skin of Bloch's gizzard shad, Nematalosa nasus (Bloch, 1795). Histopathological examination of processed skin tissues showed changes caused by A. leptosoma, such as hyperplasia and erosions of the epidermis associated dermal oedema and muscle degeneration. The host response also included an aggregation of subepithelial dense sheets of hemosiderin-laden macrophages within the dense mixed inflammatory cells. The cymothoid, A. leptosoma are serious parasites of marine fish that can cause severe economic loss in the commercially important fish species. The present study represents the first record of the parasitic cymothoid, A. leptosoma on N. nasus from India.