Metazoan Parasite Infracommunities of Rhizoprionodon acutus from Nellore Coast off Bay of Bengal Andhra Pradesh, India

Background and Objectives: Parasitic communities of Rhizoprionodon acutus were investigated from Nellore Coast (14.43EN 79.97EE), Bay of Bengal during January, 2014 and December, 2015. Special focus was given to helminth infracommunities and effect of host size and sex on its structure. Material and Methods: The parasites obtained from the host samples were enumerated and preserved for morphological analysis and ecological study using standard protocols. Results: A total of 11 taxa including 3 ectoparasites and 8 endoparasites were identified. Only, 59.2% of the fish were parasitized by one or more than one parasitic species, with an average of 2 parasites/fish. Endoparasites represented 86% of the total parasites collected with cestodes overwhelming the other parasites within the parasitic community. The number of ecto and endoparasites species per individual host ranged from 1-15 and 1-17, respectively while the mean numbers of parasite specimens per individual host were 0.38 and 1.8, respectively. There were no core and secondary species in the community and all the parasitic species occupied the rank of satellite species. Relationship between host size and parasitization revealed that medium sized (Group 2) fishes were more infected than other classes of fishes. The aggregated or over-dispersed nature of parasitic infection was exhibited by only P. floraformis (5.12), K. minuta (4.50), L. sturionis (15.1) and L. secundus (6.41).