Biodiversity and systematics of branchial cavity inhabiting fish parasitic isopods (Cymothoidae) from sub-Sahara Africa S van der Wal orcid.org/0000-0002-7416-8777 Previous qualification (not compulsory) Dissertation submitted in fulfilment of the requirements for the Masters degree in Environmental Sciences at the North-West University Supervisor: Prof NJ Smit Co-supervisor: Dr KA Malherbe Graduation May 2018 23394536 TABLE OF CONTENTS LIST OF FIGURES ................................................................................................................... VI LIST OF TABLES .................................................................................................................. XIII ABBREVIATIONS .................................................................................................................. XIV ACKNOWLEDGEMENTS ....................................................................................................... XV ABSTRACT ........................................................................................................................... XVI CHAPTER 1: INTRODUCTION ................................................................................................. 1 1.1 Subphylum Crustacea Brünnich, 1772 ............................................................ 2 1.2 Order Isopoda Latreille, 1817 ........................................................................... 2 1.3 Parasitic Isopoda .............................................................................................. 3 1.4 Cymothoidae Leach, 1814 ................................................................................ 4 1.4.1 Introduction to the Cymothoidae ......................................................................... 4 1.4.2 Life cycle and development ................................................................................ 6 1.4.3 Taxonomy and systematics ................................................................................ 6 1.4.4 Taxonomical challenges ..................................................................................... 7 1.4.5 Effects on host .................................................................................................... 9 1.5 Branchial cavity inhabiting Cymothoidae ..................................................... 12 1.6 Sub-Sahara African Cymothoids ................................................................... 13 1.7 Hypotheses, aims and objectives .................................................................. 18 1.8 Layout of dissertation .................................................................................... 20 CHAPTER 2: GENERAL METHODOLOGY ........................................................................... 21 2.1 Material collection and sites .......................................................................... 21 2.1.1 Preserved material ........................................................................................... 21 i 2.1.2 Fresh material................................................................................................... 22 2.2 Host condition ................................................................................................ 26 2.3 Morphological analysis .................................................................................. 27 2.4 Molecular characterisation ............................................................................ 32 CHAPTER 3: REVIEW OF NORILECA INDICA (MILNE EDWARDS, 1840) FROM MOZAMBIQUE ....................................................................................................................... 35 3.1 Introduction .................................................................................................... 35 3.2 Specific materials and methodology used ................................................... 35 3.3 Taxonomy ....................................................................................................... 36 3.4 Diagnosis ........................................................................................................ 36 3.5 Remarks .......................................................................................................... 36 3.6 Key to the species of Norileca Bruce, 1990 .................................................. 37 3.7 Norileca indica Milne-Edwards, 1884 ............................................................ 37 3.7.1 Material examined ............................................................................................ 38 3.7.2 Description ....................................................................................................... 38 3.7.3 Distribution ....................................................................................................... 48 3.7.4 Hosts ................................................................................................................ 49 3.8 Molecular characterisation ............................................................................ 49 3.9 Remarks .......................................................................................................... 49 3.10 Discussion ...................................................................................................... 51 CHAPTER 4: REVIEW OF ELTHUSA SCHIOEDTE AND MEINERT, 1884, FROM SOUTH AFRICA ..................................................................................................................... 52 4.1 Introduction .................................................................................................... 52 4.2 Specific materials and methodology used ................................................... 53 ii 4.3 Taxonomy ....................................................................................................... 53 4.4 Diagnosis of female ........................................................................................ 54 4.5 Remarks .......................................................................................................... 54 4.6 Key to the species of Elthusa from southern Africa .................................... 55 4.7 Elthusa raynaudii (Milne Edwards, 1840) ...................................................... 55 4.7.1 Material examined ............................................................................................ 56 4.7.2 Descriptions ...................................................................................................... 56 4.7.3 Variation ........................................................................................................... 60 4.7.4 Distribution ....................................................................................................... 60 4.7.5 Hosts ................................................................................................................ 61 4.7.6 Remarks ........................................................................................................... 62 4.8 Elthusa sp. 1 ................................................................................................... 63 4.8.1 Material examined ............................................................................................ 63 4.8.2 Descriptions ...................................................................................................... 63 4.8.3 Remarks ........................................................................................................... 69 4.9 Elthusa sp. 2 ................................................................................................... 70 4.9.1 Material examined ............................................................................................ 70 4.9.2 Descriptions ...................................................................................................... 70 4.9.3 Variation ........................................................................................................... 76 4.9.4 Remarks ........................................................................................................... 76 4.10 Molecular characterisation ............................................................................ 78 4.11 Summary of Elthusa species ......................................................................... 80 4.11.1 Discussion ........................................................................................................ 91 iii CHAPTER 6: REVIEW OF MOTHOCYA COSTA, IN HOPE, 1851, FROM KENYA AND NIGERIA ................................................................................................................................. 93 5.1 Introduction .................................................................................................... 93 5.2 Specific materials and methodology used ................................................... 94 5.3 Taxonomy ....................................................................................................... 94 5.4 Diagnosis ........................................................................................................ 95 5.5 Mothocya renardi (Bleeker, 1857) .................................................................. 95 5.5.1 Material examined ............................................................................................ 96 5.5.2 Descriptions ...................................................................................................... 96 5.5.3 Distribution ....................................................................................................