Entomology for Master Gardeners David J. Shetlar, Ph.D. The “BugDoc” The Ohio State University, OARDC & OSU Extension Columbus, OH © January, 2009, D.J. Shetlar, all rights reserved

What is Entomology? The study of insects (and their near relatives). What are insects (and near relatives)? Insects and their relatives are ARTHROPODS.

Review of Zoological Nomenclature (classifying & naming) Taxonomic Categories Phylum Class Order Family Genus Genus & species

Review of Zoological Nomenclature Taxonomic Categories Kingdom - Animalae Phylum - Arthropoda Class - Hexapoda (=Insecta) Order - Coleoptera Family - Scarabaeidae Genus - Popillia Genus & species - Popillia japonica Newman

What are some other Animal Phyla? Protozoa - single-celled animals. Platyhelminthes - flatworms, tapeworms Nematoda - roundworms Mollusca - clams, snails & slugs, squids Echinodermata - starfish, sea urchins Annelida - segmented worms (earthworms) Chordata - fish, amphibians, reptiles, birds, mammals

Phylum Nematoda – Roundworms (>15,000 species, all trophic areas)

Phylum Annelida – Segmented Worms (9,000 species, all trophic areas)

Phylum Mollusca – Snails/Slugs, Clams, Cephalopods (50,000 species, aquatic and terrestrial)

Phylum Chordata – Urocordata, Cephalocordata, Vertebrata (70,000 species)

Characteristics of the Phylum Arthropoda The segmented bodies are arranged into regions: e.g., head, thorax, abdomen in insects; cephalothorax and abdomen in arachnids and some crustaceans; head and trunk in millipedes and centipedes. The have paired appendages. They posses a chitinous exoskeletion that must be shed during growth. They have bilateral symmetry. The nervous system is ventral (belly) and the circulatory system is open and dorsal (back).

Arthropod Groups (taxa) The arthropods are divided into two large groups that exist today: The Chelicerates and The Mandibulates

Chelicerate Arthropod Characters: Pincher-like mouthparts - chelicerae - and pedipalps NO antennae Two body regions, usually - cephalothorax & abdomen Four pairs of legs Horseshoe crabs and arachnids are only living groups

Mandibulate Arthropod Characters: Mouthparts are mandibles - normally chewing sideways One or two pairs of antennae Various body region arrangements - cephalothorax & abdomen / head & trunk / head, thorax & abdomen Variable leg numbers Insects, crustaceans & myriapods

Classes of Arthropods: Chelicerates – Class Xiphosura – horseshoe crabs Class Arachnica – arachnids Mandibulates – Class Crustacea – crustaceans Class Diplopoda – millipedes Class Chilopoda – centipedes Class Symphyla – garden centipedes Class Hexapoda – insects

Orders of Arachnids Scorpiones - scorpions Pseudoscorpiones - false scorpions Opiliones - daddy-long-legs or harvestmen Acari - mites & ticks Araneae - spiders

Scorpion Tick (a mite) Pseudoscorpion Daddy-long-legs Wolf Spider

Pseudoscorpion

pedipalps & chelicerae cephalothorax abdomen Mite and Tick Body Regions

American dog tick male Blacklegged (deer) tick female

American dog tick female laying egg mass ( eggs!).

Clover mites Twospotted spider mites Predatory mite

Opiliones (=daddy-long-legs, harvestmen) cephalothoraxabdomen

pedipalp chelicera (fang) cephalothorax abdomen narrow waist Spider Anatomy

Abdomen Pedipalp Chelicera (fang) Cephalothorax Jumping Spider

Wolf spider with egg caseSpitting spider Tarantula Orbweaving spider

Black widow with egg case Brown recluse (fiddleback)

Classes of Myriapods (many legged arthropods) (all have one pair of antennae, a head region, and trunk with many pairs of legs, use trachea) Diplopoda - millipedes Chilopoda - centipedes Symphyla - garden centipedes

Myriapods Millipede (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]

Millipede (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 pillbugs Amphipoda - sand fleas, amphipods Cirripedia - barnicles Decapoda - crabs, lobster, shrimp several other minor orders

Crayfish External Morphology

Sowbugs (Isopoda), terrestrial crustaceans

Class Hexapoda (the insects) Three body regions – head, thorax, abdomen Thorax with three pairs of legs; normally two pairs of wings in adult stage Head with one pair of antennae Respiration by trachea Terrestrial & fresh water inhabitants

Lubber Grasshopper

antenna compound eye frons clypeus ocelli labrum mandible maxilla labium Lubber Grasshopper Head

pronotum coxa trochanter femur tibia tarsus spiracle mesopleuron metapleuron Lubber Grasshopper Thorax

abdominal tergites abdominal sternites cercus spiracles Lubber Grasshopper Abdomen

Insect Respiratory System Cana lily skipper (a butterfly) larvae have an almost completely transparent exoskeleton, thereby allowing a good view of the tracheal system.

Incomplete Metamorphosis Example (hairy chinch bug) egg 1st 2nd 3rd 4th 5th normal wing short wing instar instar instar instar instar adult adult Egg Nymphal Adult Stage Stage Stage

Complete Metamorphosis Example (northern masked chafer) egg 1st 2nd 3rd pupa adult instar instar instar Egg Larval Pupal Adult Stage Stage

Hexapod Orders Entognathous Hexapods – Order Protura Order Collembola Order Diplura Ectognathous apterygote Hexapods – Order Microcoryphia Order Thysanura Pterygote Hexapods – (simple metamorphosis) Order Ephemeroptera Order Odonata Order Orthoptera Order Phasmatodea Order Dermaptera Order Plecoptera Order Isoptera (simple metamorphosis cont’d) Order Mantodea Order Blattodea Order Hemiptera Order Thysanoptera Order Psocoptera Order Phthiraptera (complete metamorphosis) Order Coleoptera Order Neuroptera Order Hymenoptera Order Trichoptera Order Lepidoptera Order Siphonaptera Order Diptera

Orders of Insects (no metamorphosis) Some consider these groups insect-like and place in different class or subclass. Adults do not have wings and may molt after becoming mature Collembola - springtails Thysanura - silverfish, firebrats

Order Collembola (glue wedge) springtails Wingless (primitively) Chewing mouthparts Gradual (no) metamorphosis Adults continue to molt Feed on plants, bacteria, & fungi Important as decomposers

collophorefurcula

Order Thysanura (bristle tail) silverfish & firebrats Look like they have 3 tails – 2 cerci 1 median filament Wingless (primitively) Most are covered with scales Chewing mouthparts Gradual (no) metamorphosis Feed on organic matter, starchy materials

silverfish firebrat

Order Orthoptera (straight wing) grasshoppers & crickets Two pairs wings Forewings leathery & narrow; protect Hindwings membranous, fan-folded Some are wingless (cave crickets) Most have hind legs enlarged for jumping Females have prominent ovipositor Produce songs by rubbing wing bases together or rubbing the wings on their legs

Mating pair of grasshoppers

Female cone-nose grasshopper

Order Dermaptera (skin wing) earwigs Cerci like forceps, pinchers Defense, prey capture, mating Elongate, flattened Two pairs of wings Forewings usually short, hard Hindwings membranous, folded Few species are wingless

Seashore earwig Ringlegged earwig

Order Isoptera (equal wing) termites Social Reproductives (queens & kings) Four wings of equal size Wings twice the length of the body Wings lack cross-veins Workers & soldiers Lack wings Body white Distinguish from ants: Lack of elbowed antennae No constriction between abdomen & thorax

Swarming reproductive termites

Workers and a soldier

Order Mantodea (soothsayer) mantids / praying mantid Large ( mm) Forelegs modified for grasping prey Predatory Chewing mouthparts Gradual metamorphosis

Order Blattodea cockroaches Flattened body Long slender antennae Wings thickened, leathery Wings reduced in some species Legs modified for running Chewing mouthparts Gradual metamorphosis Feed on organic matter, stored products, plants

Order Hemiptera (half wing) true bugs & bug-like insects Formerly 2 separate orders; recently combined Suborder Heteroptera Suborders Auchenorrhyncha & Sternorrhyncha (former Homoptera)

Order Thysanoptera (fringe wing) thrips Small (most <4 mm), elongate Chewing mouthparts Small conical beak Rasping mouthparts Most with 4 wings Strap-like Fringed with long bristles Some species are wingless

Order Phthiraptera (lice without wings) Formerly 2 separate orders Suborder Mallophaga (wool eater): chewing lice Suborder Anoplura (unarmed tail): sucking lice

Head louse Head louse nit (egg)

Order Coleoptera (sheath wing) beetles Largest order in animal kingdom Chewing mouthparts Complex metamorphosis Forewings (elytra) are hardened, opaque, meet in the midline of back Hindwings membranous, folded under elytra Feed on plants, organic matter, stored products; or predatory

Order Neuroptera (nerve wing) lacewings & dobsonflies, antlions, owlflies Wings Membranous, 2 pairs Approximately equal size Many veins & cross-veins Chewing mouthparts, sometimes modified Complex metamorphosis Members of interest are predators

Order Hymenoptera (marriage wing) bees, wasps, sawflies, ants Wings: 4 membranous wings Hind pair smaller than front pair Pairs attached by row of small hooks Bees, wasps, & ants have second abdominal segment constricted & narrow; i.e. effect of “wasp-waist” Sawflies have broadly joined thorax & abdomen

Order Lepidoptera (scale wing) moths & butterflies Shingle-like scales on wings 4 wings, often colorful Complex metamorphosis Mouthparts Chewing in larva Sucking (siphoning) or none in adults Proboscis in butterflies: coiled siphon Larvae (caterpillars) – 2-5 prolegs on abdomen

Order Siphonaptera (sucking wingless) fleas Body: small, hard, laterally compressed Wingless Mouthparts: Piercing/sucking for blood in adult Chewing in larva Larvae feed on organic matter

Order Diptera (two wing) true flies Mouthparts: Sucking: modified piercing/ sucking, sponging, lapping, slashing in adult Modified chewing in larva One pair wings, on mesothorax Metathorax has 1 pair of small, knobbed appendages (halteres) Occasionally wingless