Maiden occurrence of the isopod, Norileca indica (H. Milne Edwards, 1840) in pelagic and demersal finfishes of Visakhapatnam waters along north-west Bay of Bengal

Abstract

Species of Cymothoid isopod, Norileca indica (H. Milne Edwards, 1840) was very often observed to infest the fishes. Detailed morphological features of the parasitic species are presented along with their incidence and prevalence in the three host fishes from June, 2013 - March, 2014. Prevalence, mean intensity and abundance were 39.03±8.04%, 1.13±0.00 and 0.44±0.10 for R. kanagurta, 40.34±1.73%, 1.35±0.12 and 0.54±0.02 for S. insidiator and 45.43±5.68%, 1.25±0.07 and 0.56±0.04 for N. randalli. Sex of the host was found to have an effect on prevalence and abundance of the parasite, with higher values reported from females. High prevalence and abundance of the parasite during post trawl ban period coincided with the peak landings of their hosts. Prevalence and abundance were relatively higher in smaller specimens of the host fishes. This is the first instance wherein cymothoid isopod, N. indica has been recorded in finfishes from the waters of Visakhapatnam along north-west Bay of Bengal.