Jeyaraney Kathirithamby, Department of Biology and St Hugh’s College, University of Oxford, UK.

• Preface xiiiAbout the Companion Website xvii1 Order Strepsiptera 11.1 Introduction 11.2 Are Strepsiptera Parasites or Parasitoids? 101.3 Trichotomous Hypothesis of Insect Parasitoids 111.4 Metamorphosis 14References 162 History of Strepsiptera 23References 333 Collection 393.1 Introduction 393.2 Stylopised Leaf- and Planthoppers 393.3 Stylopised Eusocial Wasps 403.4 Stylopised Grasshoppers/Crickets/Mantids 413.5 Stylopised Silverfish 42References 434 Phylogeny 454.1 Phylogenetic Position on the Tree of Life 454.2 Phylogeny of Strepsiptera 494.3 Mitochondrial Genomes 53References 565 Fossil Species 635.1 Introduction 635.2 Families: Protoxenidae, Phthanoxenidae and Cretostylopidae 675.3 Family Mengeidae 695.4 Planidia from Cretaceous Amber 715.5 Planidium from Eocene Baltic Amber 725.6 Males in Eocene Baltic Amber 725.7 Males in Compressed Shale 735.8 Male in Fushun Amber 765.9 Males in Miocene Amber 765.10 Male in Madagascar Copal 805.11 Fossil Strepsiptera and Their Hosts 805.12 Biology of Fossil Strepsiptera 81References 826 First Instar Free- Living Planidium 876.1 Introduction 876.2 History 896.3 Biology and Life History 906.4 Birth of Planidia 936.5 Locomotion 936.6 Entry into Host 946.7 Host Defence 976.8 Moulting After Host Entry 976.9 Dispersal 986.9.1 Phoretic Transmission 986.9.2 Mass/Direct Release 1016.10 Planidia Found in Unusual Destinations 101References 1027 Endoparasitic Larval Stages 1117.1 Introduction 1117.2 Apolysis Without Ecdysis 1117.3 Life History 1157.3.1 Endoparasitic Second Instar Larva 1157.3.2 Endoparasitic Third Instar Larva 1157.3.3 Endoparasitic Fourth Instar Larva 1167.4 Internal Development 1187.5 Emergence and Extrusion Through Host Cuticle 1217.6 Avirulence 1217.7 Immune Defence 1237.7.1 Masquerading as ‘Self’ 123References 1268 Pupal Stage 1338.1 Introduction 1338.2 Free – Living Puparium of Male and Female Mengenillidae 1338.3 Partially Endoparasitic Male Puparium of Stylopidia 1368.4 Pre-formed ‘Line of Weakness’ in Male Puparium of Stylopidia 1378.5 Development of the Eye in Male Pupa of Stylopidia 1408.6 Development of the Reproductive System in Male Pupa of Stylopidia 1418.7 Absence of the Pupal Instar in Female Stylopiformia 141References 1459 Adult Male 1499.1 Introduction 1499.2 Biology and Life History 1529.2.1 Head 1529.2.2 Eyes 1539.2.3 Thorax 1579.2.4 Abdomen 1619.2.5 Reproductive System 1639.3 Emergence of Free- Living Male from the Puparium 1679.3.1 Contractions 1679.3.2 Frontal Sac 1679.3.3 Mandibles 168References 16910 Free- Living Female Mengenillidae and Neotenic Female Stylopidia 17710.1 Introduction 17710.2 Free- Living Female Mengenillidae 17910.3 Endoparasitic, Neotenic Female Stylopidia 18010.3.1 Reproductive System in Stylopidia 18410.4 Metamorphic Transformation of the Cephalothorax 18610.4.1 Developmental Process in Stylopidia 19210.5 Multiple Cuticles of the Endoparasitic, Neotenic Female Stylopidia 19510.6 Brood Canal System in Stylopidia 19610.6.1 Invagination in the Brood Canal of Stylops 19810.7 Birth of Planidia in Mengenillidae and Stylopidia 19910.8 Nassonov’s Glands 19910.8.1 Structure of Nassonov’s Glands 19910.8.2 Pheromone 20210.8.3 Structure of the Pheromone 203References 20411 Mating 21311.1 Introduction 21311.2 Maturation of Male and Female 21311.3 Female ‘Calling’ Behaviour and Attraction 21411.4 Adult Male Emergence and Behaviour Before Mating 21711.5 Behaviour of Male During Mating 21811.6 Insemination 21911.6.1 Traumatic Insemination in Mengenillidae 22311.6.2 Brood Canal Insemination in Stylopidia 22311.7 Receptor Systems and Signals During Sexual Communication 22511.7.1 Antennae and Maxillary Palps 22511.7.2 Tarsi 22511.7.3 Hairs on Aedeagus 22611.8 Reproductive Synchrony 226References 22812 Basal Extant Families: Family Bahiaxenidae 23512.1 Introduction and Taxonomy 235Reference 23513 Family Mengenillidae 23713.1 Introduction 23713.2 Taxonomy 24213.3 Biology and Life History 24513.4 Birth and Emergence of Planidia from a Free- Living, Neotenic Female 24713.4.1 Neotenic Female that Remains in the Puparium 24713.4.2 Birth and Emergence of Planidia from a Female that Remains in the Puparium 24813.5 Hosts 24913.6 Entomophagous Parasites 25013.7 Nematode Parasites 251References 25214 Suborder Stylopidia: Family Corioxenidae 25714.1 Introduction 25714.2 Taxonomy 25714.3 Extrusion of the Cephalotheca and Cephalothorax 26014.4 Emergence of Male 26214.5 Unusual Insemination 26214.6 Emergence of Planidia 26314.7 Unusual Life Cycle and Super-stylopisation in Blissoxenos 26414.8 Dispersal of Planidia 26714.9 Morphological Changes of Stylopised Corioxenidae 26714.10 Corioxenidae as Biocontrol Agents 268References 26815 Infraorder Stylopiformia: Myrmecolacidae 27315.1 Introduction 27315.2 Taxonomy 28115.3 Heterotrophic Heteronomy 28515.4 Behaviour of Stylopised Ants 28815.5 Host- Seeking Behaviour of Planidia with Dimorphic Hosts 29015.6 Cryptic Diversity 29115.7 Partitioning of Genetic Diversity and Patterns of Host Specificity 29215.8 Biogeography 29915.9 Origin of Caenocholax in United States 30015.10 Multi-parasitism 30115.11 Myrmecolacidae as Biocontrol Agents 301References 30316.1 Family Lychnocolacidae 31316.1.1 Introduction 313References 31416.2 Family Bohartillidae 31616.2.1 Introduction 316References 31717 Family Stylopidae 31917.1 Introduction 31917.2 Taxonomy 32217.3 Prevalence of Stylopisation 32417.4 Morphological Changes in Stylopised Hosts 32417.5 Pheromone 32717.6 Behavioural Changes in Stylopised Hosts 32917.7 Protandry 33017.8 Phoretic Transmission 33317.9 Host- seeking by Planidia 33717.10 Super-stylopisation 33717.11 Multi-parasitisim 33817.12 Cryptic Species and Host Specificity 339References 34118 Family Xenidae 35118.1 Introduction 35118.2 Taxonomy 35418.3 Inquilines 35918.4 Life Cycle of Xenos in Relation to Colony Cycle of Host 36018.5 Infective Stages of Host 36418.6 Stylopisation of Polistes in Native and Invasive Ranges 36518.7 Prevalence 36618.8 Morphological Changes in Styopised Hosts 36918.9 Behavioural Changes in Stylopised Hosts 37218.9.1 Extranidal Aggregations 37218.9.2 Extended Phenotype 37518.10 Voltinism 37618.11 Extension of Life Cycle of Stylopised Host 37818.12 Virulence 38118.13 Encapsulation 38318.14 Effect of Stylopisation on Status Badges 38418.15 Cuticular Hydrocarbons in Stylopised Hosts 38518.16 Mechanism of Transfer of Planidia to Nests 38518.16.1 Phoretic Transmission 38618.16.2 Mass/Direct Release 39018.17 Super-stylopisation 39118.18 Co- Habitation 39218.19 Phylogeny, Cryptic Species and Host Specificity 392References 39419 Family Elenchidae 41719.1 Introduction and History 41719.2 Taxonomy 41919.3 Biology and Life History 42119.4 Morphological Changes in Stylopised Hosts 42319.5 Super-stylopisation 42419.6 Mulit-parasitism 42519.7 Cryptic Species and Host Specificity 42519.8 Elenchus as Biocontrol Agents 42619.9 Wolbachia Endosymbionts 426References 42820 Family Halictophagidae 43520.1 Introduction 43520.2 Taxonomy 43620.3 Biology and Life History 44120.4 Morphological Changes in Stylopised Hosts 44420.5 Super-stylopisation 44420.6 Multi-parasitism 44420.7 Halictophagidae as Biocontrol Agents 44520.8 Wolbachia Endosymbionts 446References 449Index 459