1Entomology 462Arthropod GroupsDavid J. Shetlar, Ph.D.The “BugDoc”The Ohio State University,OARDC & OSU ExtensionColumbus, OHWhat is Entomology?The study of insects(and their near relatives).What are insects (and near relatives)?Insects and their relatives areARTHROPODS.2Review of Zoological Nomenclature(classifying & naming)Taxonomic CategoriesPhylumClassOrderFamilyGenusGenus & speciesReview of Zoological NomenclatureTaxonomic CategoriesKingdom -AnimalaePhylum -ArthropodaClass -HexapodaOrder -ColeopteraFamily -ScarabaeidaeGenus -PopilliaGenus & speciesPopilliajaponicaNewman3Characteristics of the PhylumArthropodaThe segmented bodies are arranged into regions, calledtagmata(e.g., head, thorax, abdomen).The paired appendages (e.g., legs, antennae) are jointed.They posses achitinous exoskeletionthat must be shed during growth.They have bilateral symmetry.The nervous system is ventral (belly) and the circulatory system is open and dorsal (back).What are some other Animal Phyla?Protozoa -single-celled animals.Platyhelminthes-flatworms, tapewormsNematoda-roundwormsMollusca-clams, snails & slugs, squidsEchinodermata-starfish, sea urchinsAnnelida-segmented worms (earthworms)Chordata-fish, amphibians, reptiles, birds, mammals4Arthropod Groups (taxa)The arthropods are divided into two large groups that exist today:The CheliceratesandThe MandibulatesChelicerate Arthropod Characters:Pincher-like mouthparts -chelicerae - and pedipalpsNO antennaeTwo body regions, usually -cephalothorax & abdomenFour pairs of legsHorseshoe crabs and arachnids are only living groups5MandibulateArthropod Characters:Mouthparts are mandibles -normally chewing sidewaysOne or two pairs of antennaeVarious body region arrangements -cephalothorax& abdomen / head & trunk / head, thorax & abdomenVariable leg numbersInsects, crustaceans &myriapodsOrders of ArachnidsScorpionida-scorpionsPseudoscorpionida-false scorpionsOpiliones-daddy-long-legs or harvestmenAcari-mites & ticksAraneida-spiders6ScorpionTick(a mite)PseudoscorpionDaddy-long-legsWolfSpiderpedipalp (chelate)cheliceracephalothorax abdomenScorpion Anatomy7cheliceraeeyes pedipalp8Pseudoscorpionpedipalps &cheliceraecephalothoraxabdomenMite and Tick Body Regions9American dog tick maleBlacklegged (deer) tick femaleAmerican dog tick female laying egg mass (1000-2000 eggs!).10Clover mitesTwospotted spider mitesPredatory miteOpiliones (=daddy-long-legs)cephalothorax abdomen11pedipalpchelicera (fang)cephalothoraxabdomennarrow waistSpider AnatomyAbdomenPedipalpChelicera (fang)CephalothoraxJumping Spider12Wolf spider with egg case Spitting spiderTarantulaOrbweaving spiderBlack widow with egg caseBrown recluse(fiddleback)13Classes of Myriapods(many legged arthropods)(all have one pair of antennae, a head region, and trunk with many pairs of legs, use trachea)Diplopoda - millipedesChilopoda - centipedesSymphyla - garden centipedesMyriapodsMillipede (Diplopoda)Two pair of legs per visible segment, attached under body.Centipede (Chilopoda)Pair of fangs under head, one pair legs per visible segment - attached to side of body.Symphylan (Symphyla)[garden centipede]No fangs, no eyes, legs attached to side of body.[one pair of antennae, head & trunk regions, trunk with many pairs of legs]14Millipede (Diplopoda)Centipede (Chilopoda)Garden centipede (Symphyla)Classes of Crustacea(mostly marine, fresh water, a few terrestrial)(all have two pair of antennae, five or more pairs of legs, segmented abdominal appendages, head & trunk or cephalothorax & abdomen body arrangement, have gills)Isopoda - sowbugs or pillbugsAmphipoda - sand fleas, amphipodsCirripedia - barniclesDecapoda - crabs, lobster, shrimpseveral other minor orders15Crayfish cephalothorax(Decapoda)Sowbug (Isopoda), a terrestrial