ENDOPTERYGOTES
ENDOPTERYGOTA (=HOLOMETABOLA) Major Change in Life Pattern Exopterygota Egg Nymph Adult Endopterygota Egg Larva Pupa Adult
Changes needed in becoming an endopterygote 1. Larval musculature - not functional in adult 2. Change in gut 3. Mouthpart modifications
Are there intermediates? Aleyrodidae - whiteflies (Homoptera) - histolysis of nymphal organs - wing development is external Thrips (Thysanoptera) - histolysis of nymphal muscles - wing development is external
Metamorphosis - how do they do it?
Metamorphosis - how do they do it?
Metamorphosis - waste products Deamination Protein breakdown Ammonia - toxic Uric acid Meconium
Predominance of the Endopterygota
Phylogeny of Insects Insecta ? Archaeognatha Thysanura Paleoptera Orthopteroids Megaloptera Pterygota Rhaphidioptera Neuroptera Neoptera Hemipteroids Coleoptera ? Strepsiptera Endopterygota Diptera Mecoptera Siphonaptera Trichoptera Lepidoptera Hymenoptera
Neuropteroid Orders ? Megaloptera Megaloptera Rhaphidioptera Neuroptera Neuroptera Coleoptera ? Strepsiptera Strepsiptera Endopterygota Diptera Mecoptera Siphonaptera Trichoptera Lepidoptera Hymenoptera
NEUROPTEROID ORDERS NEUROPTERA (antlions, lacewings) MEGALOPTERA (Dobsonflies, alderflies) RHAPHIDIOPTERA (snakeflies) STREPSIPTERA (twisted wing parasites)
Hexapoda Insecta Pterygota Neoptera Holometabola Apterygotes 500 400 300 200 100 0 Silurian Devonian Carboniferous Permian Triassic Jurassic Cretaceous Entognatha Archaeognatha Hexapoda Zygentoma = Thysanura) Ephemeroptera Insecta Odonata Plecoptera Embiodea Pterygota Zoraptera Dermaptera Grylloblattodea ? Mantophasmatodea Orthoptera Phasmatodea Blattaria Isoptera Mantodea Neoptera Psocoptera Phthiraptera Thysanoptera Hemiptera Coleoptera Rhaphidioptera Megaloptera Neuroptera Hymenoptera Holometabola Mecoptera Siphonaptera Diptera Apterygotes Strepsiptera Trichoptera Paleoptera Lepidoptera Hemimetabolous Holometabolous
Molecular evidence Mecoptera Siphonaptera Diptera Lepidoptera Trichoptera Neuroptera Rhaphidionaptera Megaloptera Coleoptera Strepsiptera Hymenoptera HEMIMETABOLOUS Carboniferous Permian Triassic Jurassic Cretaceous Weigman et al, 2009
Comparison of Phylogenies Mecoptera Siphonaptera Megaloptera Diptera Rhaphidioptera Lepidoptera Trichoptera Neuroptera Neuroptera Rhaphidioptera Coleoptera Megaloptera ? Strepsiptera Coleoptera Diptera Strepsiptera Mecoptera Siphonaptera Hymenoptera Coleoptera Trichoptera Rhaphidioptera Lepidoptera Megaloptera Neuroptera Hymenoptera Hymenoptera Mecoptera Siphonaptera Diptera Strepsiptera Trichoptera Lepidoptera
Hexapod Orders Strepsiptera Strepsi - twisted, ptera - wing Number of Species 500 Common names Twisted wing parasites, strepsipterans Typical habitats Parasites of other insects Distinguishing characteristics -reduced life stages -triungulin larva -forewings are halteres -wings with few veins -females - breed while larval Other features
Strepsiptera - features Males - ‘ raspberry eye’ Forewings = halteres
Moults - 2nd and 3rd instar Strepsiptera - Life cycle Oral secretions soften host cuticle Host endocuticle detaches and surrounds parasite Seeks host Moults - 2nd and 3rd instar -legless grub Triungulin (1st instar larva) hatches Pupation Host cuticle Female larval cuticle Male leaves to seek mate Mating Cephalothorax Female stays in host Brood canal Genital pore
Strepsiptera - mating = oocyte sperm
Moults - 2nd and 3rd instar Strepsiptera - Life cycle Oral secretions soften host cuticle Host endocuticle detaches and surrounds parasite Seeks host Moults - 2nd and 3rd instar -legless grub Triungulin (1st instar larva) hatches Pupation Host cuticle Female larval cuticle Male leaves to seek mate Mating Cephalothorax Female stays in host Brood canal Genital pore
Hexapod Orders Neuroptera Neuro - nerve, ptera - wing Number of Species 5000 Common names Lacewings, antlions Typical habitats Variable Distinguishing characteristics -numerous crossveins in wing -larvae with incomplete gut -most primitive endopterygote -predaceous larvae Other features
Neuroptera - who are they? Lacewings Larvae - predatory Adults - predatory or pollen feeders
Neuroptera - who are they? Antlions
Neuroptera - who are they? Antlions Larvae construct pits to trap prey
Neuroptera - who are they? Mantispidae -convergent evolution with Mantodea
Neuroptera - who are they? Sisyridae - spongilla flies
Hexapod Orders Megaloptera Megalo - large, ptera - wing Number of Species 300 Common names Dobsonflies, alderflies Typical habitats Variable , larvae - aquatic Distinguishing characteristics -predatory larvae with complete gut -anal fold in wing Other features -pronotum slightly extended -mandibles in adult not used
Megaloptera - who are they? Adult Larva - “hellgrammite”
Megaloptera - who are they? Life cycle Eggs hatch & larvae drop into stream/pond Eggs laid overhanging water Adults mate Pupate in earthen cell Hellgrammite larva
Hexapod Orders Raphidioptera Raphidio - ????, ptera - wing Number of Species 200 Common names snakeflies Typical habitats Forests - found west of Rockies Distinguishing characteristics -greatly extended pronotum -adults and larvae predatory Other features