Morphology, diversity, taxonomy and phylogeny of Tylenchidae (Nematoda, Tylenchomorpha) Xue Qing Promoter: Prof. Dr. Wim Bert Thesis submitted in fulfillment of the requirements for the degree of Docter in Science, Biology Examination Committee Prof. Wim Bert Promoter, Ghent University, Belgium Prof. Tom Moens Chairman, Ghent University, Belgium Prof. Annemieke Verbeken Secretary, Ghent University, Belgium Prof. em. Etienne Geraert Ghent University, Belgium Prof. Olivier De Clerck Ghent University, Belgium Dr. Matthew Back Harper Adams University, UK Table of contents Acknowledgments ................................................................................................................................... 1 Samenvatting ........................................................................................................................................... 2 Summary ................................................................................................................................................. 5 Chapter I: General introduction .............................................................................................................. 7 Background .......................................................................................................................................... 8 Classification ........................................................................................................................................ 8 Ecology .............................................................................................................................................. 12 Phylogeny and evolution ................................................................................................................... 14 General morphology ......................................................................................................................... 18 Lip region ....................................................................................................................................... 18 Cuticle and lateral region .............................................................................................................. 20 Stylet .............................................................................................................................................. 23 Female reproductive system ......................................................................................................... 25 Male copulatory system ................................................................................................................ 28 Tail ................................................................................................................................................. 29 Objectives and outline of the thesis .............................................................................................. 32 Chapter II: Description of one new, and new records of three known species of genus Malenchus Andrássy, 1968 (Nematoda: Tylenchidae); with notes on the development of the amphidial aperture ............................................................................................................................................................... 39 Abstract ............................................................................................................................................. 40 Introduction ....................................................................................................................................... 41 Materials and methods ..................................................................................................................... 42 Samples collecting and processing ................................................................................................ 42 Morphological characterization .................................................................................................... 42 Molecular characterization ........................................................................................................... 43 Results ............................................................................................................................................... 48 Discussion .......................................................................................................................................... 60 Molecular characterization and phylogeny ................................................................................... 60 Remarks on amphidial aperture development ............................................................................. 61 Chapter III: Molecular phylogeny of Malenchus and Filenchus ............................................................ 67 Abstract ............................................................................................................................................. 68 Introduction ....................................................................................................................................... 69 Materials and methods ..................................................................................................................... 69 Taxonomic sampling ...................................................................................................................... 69 Morphological analyses ................................................................................................................. 70 Molecular analysis ......................................................................................................................... 70 Results ............................................................................................................................................... 72 Ultrastructure of body cuticle and annulations ............................................................................ 72 Ultrastructure of lateral region ..................................................................................................... 75 Phylogeny of Malenchus and Filenchus ......................................................................................... 76 Character evolution of annuli and amphideal fovea ..................................................................... 79 Discussion .......................................................................................................................................... 80 Chapter IV: Redefinition of genus Malenchus Andrássy, 1968 (Tylenchomorpha: Tylenchidae) with additional data on ecology .................................................................................................................... 92 Abstract ............................................................................................................................................. 93 Introduction ....................................................................................................................................... 94 Materials and methods ..................................................................................................................... 94 Result and discussion ........................................................................................................................ 95 Taxonomic overview ..................................................................................................................... 95 Geographic distribution ................................................................................................................. 96 General morphology...................................................................................................................... 97 Cuticle annulation ....................................................................................................................... 100 Cuticle ultrastructure .................................................................................................................. 101 Head region ................................................................................................................................. 103 Lateral region .............................................................................................................................. 107 Prophasmid ................................................................................................................................. 109 Reproductive system ................................................................................................................... 111 Revised generic definitions ......................................................................................................... 115 Observations on ecology ............................................................................................................. 117 Chapter V: 3D printing in zoological systematics: an integrative taxonomy of Labrys chinensis gen. nov., sp. nov. (Nematoda: Tylenchomorpha) ...................................................................................... 128 Abstract ........................................................................................................................................... 129 Introduction ..................................................................................................................................... 130 Materials and methods ................................................................................................................... 131