The parasite assemblage of Scomber japonicus (Houttyun, 1782) off South Africa Joshua Paul Hendricks Dissertation submission in fulfilment of the requirements for the degree of Master of Science Marine research institute, Department of Biological Science Town University of Cape Town 2018Cape of Supervisors:University Dr Cecile Reed 1,3 and Dr Carl van der Lingen2,3 1Department of Biological Sciences, University of Cape Town, Private Bag X3, Rondebosch, 7701, Cape Town, South Africa 2Department of Agriculture, Forestry and Fisheries, Branch: Fisheries Management, Private Bag X2, Vlaeberg, 8012, Cape Town, South Africa 3Marine Research Institute and Department of Biological Sciences, University of Cape Town, Private Bag X3, Rondebosch, 7701, Cape Town, South Africa 1 The copyright of this thesis vests in the author. No quotation from it or information derived from it is to be published without full acknowledgementTown of the source. 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SIGNATURE: NAME: Joshua Paul Hendricks STUDENT NUMBER: HNDJOS003 2 Table of Contents DECLARATION ...................................................................................................................................... 2 ABSTRACT .............................................................................................................................................. 6 ACKNOWLEDGEMENTS ...................................................................................................................... 9 INTRODUCTION .................................................................................................................................. 11 Literature review ................................................................................................................................. 11 Introduction to Scomber japonicus ................................................................................................. 11 Scomber japonicus in Southern Africa ........................................................................................... 13 Parasitism as a lifestyle ................................................................................................................... 15 Parasite/human interactions ............................................................................................................ 16 Health impacts................................................................................................................................. 16 Economic significance .................................................................................................................... 17 Ecological significance ................................................................................................................... 18 Parasite diversity ............................................................................................................................. 19 Marine parasitology in South Africa ............................................................................................... 26 Aims and objectives ........................................................................................................................ 27 METHODOLOGY.................................................................................................................................. 28 Study site ............................................................................................................................................. 28 Sampling ............................................................................................................................................. 29 Fish and parasite processing ............................................................................................................... 30 Fish processing ................................................................................................................................ 30 3 Parasite processing .......................................................................................................................... 32 Host biological factor analysis ........................................................................................................ 34 Statistical analysis ............................................................................................................................... 35 Exploratory Data Analysis .............................................................................................................. 35 Determinants of infection................................................................................................................ 37 Parasite community analysis ........................................................................................................... 39 Gill parasite analysis ....................................................................................................................... 40 RESULTS ............................................................................................................................................... 42 Exploratory Data Analysis .................................................................................................................. 42 Host biological factor analysis ............................................................................................................ 44 Parasite assemblage............................................................................................................................. 47 Parasite community analysis ............................................................................................................... 54 Determinants of infection.................................................................................................................... 57 Anisakis simplex .............................................................................................................................. 57 Pseudokuhnia minor ....................................................................................................................... 61 Lecithocladium sp. .......................................................................................................................... 65 Opechona bacillaris ........................................................................................................................ 67 Rhadinorhynchus pristis ................................................................................................................. 69 Cyst 1 .............................................................................................................................................. 73 Gill parasite analysis ........................................................................................................................... 77 Global comparison of the parasite assemblages of Scomber japonicus populations .......................... 78 4 DISCUSSION ......................................................................................................................................... 81 Scomber japonicus parasites ............................................................................................................... 81 Myxozoa.......................................................................................................................................... 81 Monogenea ...................................................................................................................................... 83 Cestoda ............................................................................................................................................ 91 Nematoda ........................................................................................................................................ 92 Digenea ........................................................................................................................................... 87 Acanthocephala ............................................................................................................................... 94 Copepoda ........................................................................................................................................ 96 Community analysis ............................................................................................................................ 97 LIMITATIONS AND FURTHER RESEARCH .................................................................................. 100 REFERENCES.....................................................................................................................................