Out of Chaos, Order(s) 2017 Master Gardener College Erwin Duke Elsner Consumer Horticulture/Small Fruit Extension Educator 520 W. Front Street elsner@anr.msu.edu 231-922-4822 Phylum Arthropoda Insects and their relatives Phylum Arthropoda Insects and their relatives Lots and lots of relatives Arthropods dominate the planet by number of species Estimates vary, but conservatively: 6 to 10 million species Over 80 % of all animal species 900,000 described species of insects Millions more undescribed or undiscovered United States estimates: 91,000 insect species described 73,000 yet to be described 23,700 beetles 19,600 flies 17,500 bees, wasps and ants 11,500 moths and butterflies Portions of animal kingdom Portion of all known species 1
Time for a little history Carolus Linnaeus 1707-1778 Founder of binomial nomenclature that is the basis of taxonomy Words and Terms matter Nomenclature Classification Taxonomy Systematics Example of Classification: ABCDEFGHIJKLMNOPQRSTUVWXYZ Example of Classification: ABCDEFGHIJKLMNOPQRSTUVWXYZ BCDFGHJKLMNPQRSTVWXYZ AEIOU and sometimes Y Example of Classification: ABCDEFGHIJKLMNOPQRSTUVWXYZ AEFHIKMNTVWXYZ BCDGJOPRSU Taxonomy: The science of classification; laws and principles covering the classifying of objects A system of arranging animals and plants into natural, related groups based on some factor common to each, as structure, embryology, or biochemistry 2
Systematics: The science or a method of classification, especially taxonomy Based on evolutionary principles and lineages of groups of species Ideally Taxonomic groupings should represent the phylogenetic relationships of organisms Representative of true relatedness of species- phylogenetics Phylogeny: The lines of descent or evolutionary development of any plant or animal species The origin and evolution of a division, group or race of animals or plants Reality In most cases, the genetic information is not available and groupings are based on observable characteristics A binomial Genus and species Unique to each living organism Scientific Names This butterfly is known as Papilio glaucus, around the world, in any language Scientific Name Rules Genus name always capitalized Species name never capitalized Italicized OR Underlined Papilio glaucus Papilio glaucus 3
Species Common Names Same common name may be used for numerous species Some species have official common names accepted by all authorities Papilio glaucus = Eastern Tiger Swallowtail Higher Classification Groups of related genera placed in families family Papilionidae contains Papilio glaucus Papilio canadensis Papilio troilus Battus philenor Eurytides marcellus and many more Higher Classification Groups of related families placed in orders order Lepidoptera contains Higher Classification Groups of related orders placed in classes class Insecta (Hexapoda) contains family Papilionidae family Saturniidae family Tortricidae family Noctuidae family Pyralidae and many more order Lepidoptera order Diptera order Coleoptera order Orthoptera order Hymenoptera and many more Higher Classification Groups of related classes placed in phylums phylum Arthropoda contains class Insecta class Arachnida class Diplopoda class Chilopoda class Malacostraca and many more What Higher Classification Can Tell You If you can identify an arthropod to a class: You might know if is predatory or not Not much more 4
What Higher Classification Can Tell You If you can identify an arthropod to an order: What Higher Classification Can Tell You If you can identify an arthropod to an order: You will know its type of metamorphosis You will likely know what type of mouthparts it has You may know what types of pesticides might work against it You may know its typical habitat You may know if it is predatory or not It will be easier to identify to a family level What Higher Classification Can Tell You If you can identify to a family: class Hexapoda class Arachnida class Diplopoda class Chilopoda class Malacostraca and many more Nomenclature: The system or set of names used in a specific branch of learning or activity, as in biology for plants and animals Essentially, the rules for naming organisms Nomenclature Ending Rules Phylums No rules Classes No rules Orders No rules, some patterns Phylum Arthropoda Class Insecta Order Lepidoptera Family Papilionidae Genus Papilio Species glaucus The eastern tiger swallowtail Families Genus & species idae No rules 5
Phylum Arthropoda Class Insecta Order Homoptera Family Cicadellidae Genus Empoasca Species fabae The potato leafhopper Splitters & Lumpers Authorities frequently disagree Nomenclature and organization may vary in references Important in real world?? Literally dozens of very similar species The Challenge of Identification Literally hundreds of very similar species Minute characteristics Minute characteristics Mimicry Mimicry The Challenge of Identification Which of these two insects would you be willing to capture in your bare hand? Mistakes are common 6
Mistakes are common Mistakes are common Non migratory mimic Viceroy vs. migrating model Monarch Basic Characteristics of Arthropods segmented bodies groups of segments organized into body regions jointed appendages exoskeleton & molting cold blooded physiology diverse modifications Arthropod exoskeletons External protective & supporting structure Varies in thickness, flexibility Surface is non-living material Must be shed & replaced for growth Arthropod exoskeletons Exoskeleton of immature stages is often thinner More flexible, stretchable Outer layer is still a dead tissue that must be shed and replaced for growth Molting Process of shedding the exoskeleton New, larger or modified exoskeleton is formed beneath the old one 7
Metamorphosis A change in form and/or function as an insect grows and passes through stages Gradual or Simple Metamorphosis Immature stages outwardly similar to adults Change may be minor or substantial, with different names: Simple Incomplete Complete Details may change as the creature grows and matures Complete Metamorphosis Arthropod Identification & Classification Classification is based on characteristics Type of metamorphosis Type of mouthparts Antennal forms Leg characteristics Wing type and number Many other characters Major classes of Athropods A r t h r o p o d s Chilopoda Centipedes Diplopoda Millipedes Arachnida Spiders, mites, ticks Malacostraca Lobsters, shrimp, sow bugs Head w/antennae + elongated trunk w/1 pair of legs per segment Head w/antennae + elongated trunk w/2 pairs of legs per segment Cephalothorax w/4 pairs of legs + abdomen Cephalothorax w/5 pairs of legs, 2 pair antennae + abdomen Insecta Head w/antennae + thorax w/3 pairs of legs + abdomen 8
Class Chilopoda - Centipedes 2 tagmata, a cephalothorax & abdomen Generally flattened Numerous pairs of legs, 1 pair per segment; 1 st pair a poison fang 1 pair of antennae Chewing mouthparts predators Class Chilopoda - Centipedes Class Diplopoda - Millipedes 2 tagmata, a cephalothorax & abdomen Generally cylindrical Numerous pairs of legs, 2 pair per segment 1 pair of antennae Chewing mouthparts scavengers Class Diplopoda - Millipedes Class Malacostraca (Crustacea) Crabs, lobsters, crayfish, sowbugs 2 tagmata, a cephalothorax & abdomen 4 to 7 pairs of legs 2 pairs of antennae Sowbugs, pillbugs 2 tagmata, a cephalothorax & abdomen But hard to discern the division point 7 pairs of legs Omnivorous scavengers Order Isopoda 9
2 tagmata, a cephalothorax & abdomen 4 pairs of walking legs No antennae Chelicerate mouthparts Class Arachnida Arachnida Morphology Two body parts: Cephalothorax and Abdomen Spiders, ticks, mites Arachnida Morphology Mites and Ticks - hard to discern the cephalothorax from the abdomen Spiders, order Araneae Spiders, order Araneae Many families, hard to key out Mostly generalists, some are searchers Kill prey with venom Some kill prey larger than themselves Some use silk for capturing prey Order Opiliones - Harvestmen 2 tagmata, a cephalothorax & abdomen, appearing fused 4 pairs of walking legs No antennae Minor predators & scavengers 10
Arthropod Orders: Acari Order Scorpiones Mites and ticks Chelicerate mouthparts (diff. form of piercing-sucking) Gradual metamorphosis 4 pairs of walking legs (1 st stage has 3 pair) No antennae, no wings Body divisions not obvious, a cephalothorax and abdomen Order Pseudoscorpiones Class Insecta (Hexapoda) 3 body regions, head, thorax & abdomen 0-3 pairs of jointed legs Some species with wings 1 pair of antennae Mouthparts modified in various ways Incredibly diverse and successful Insect Morphology Three body parts: Head, thorax and Abdomen Insect Morphology Three body parts: Head, thorax and Abdomen 11
Basic Insect Morphology Exercise 1 Hand lens technique Sort your arthropods to class level See if you can sort Arachnids to order level Class Insecta (Hexapoda) Arthropods 3 body regions, head, thorax & abdomen Insects Spiders, mites, ticks & Scorpions Centipedes Millipedes Shrimps, Crabs & Sow bugs 0-3 pairs of jointed legs Diptera Flies Some species with wings Lepidoptera Hymenoptera Moths Bees, Wasps Coleoptera Beetles 1 pair of antennae Mouthparts modified in various ways Incredibly diverse and successful Hemiptera Homoptera Plus 21 more! Plant bugs Aphids Orthoptera, Dermaptera, Isoptera, Thysanoptera..... Basic Insect Morphology Basic Insect Morphology 12
Insect Morphology Three body parts: Head, thorax and Abdomen Parts of the head Head features Mouthparts Types of mouthparts Antennae Eyes Chewing Piercing/sucking Sponging/lapping Siphoning Chewing Mouthparts Opposable jaws called mandibles Several accessory parts for food manipulation Piercing-Sucking Mouthparts Delicate stylets in a sheath (proboscis) Ingests only fluids 13
Mouthparts Piercing/Sucking Piercing-Sucking Mouthparts Proboscis may tuck under head or thorax when not in use Sponging/Lapping Mouthparts Ingests only fluids Siphoning Mouthparts Ingests only fluids Coiled when not in use Antennae Sensory functions Vary widely in form and size Compound Eyes Dozens to thousands of facets Some species can detect ultra-violet wavelengths 14
Ocelli Only type of eyes on many caterpillars Thorax features Three pairs of jointed legs on the thorax Many modifications of form and function Leg Modifications Jumping Raptorial Thorax features Two pairs of wings on thorax of adults of most species Front pair thickened or leathery in many groups Digging Detail of wings very important for identification Wings Wing venation aids in ID Wings may be: Membranous Leathery Hard Hairy Scale covered Foldable Brachypterous Vestigial Absent 15
Abdomen features Often hidden under wings on adults Segmentation often visible Terminal segments modified for mating and egg laying functions May bear false legs on immature stages Insect Stages, Growth & Development Insects typically: Lay eggs Pass through several immature stages Mate after reaching adulthood Gradual or Simple Metamorphosis Gradual Metamorphosis Immatures are called nymphs Nymphs similar to adults Wings develop externally Same type of mouthparts through all active stages eggs nymph Developing wings appear as small projections from the thorax, enlarging at molts Wings are not fully developed or functional until the adult stage nymph adult Incomplete Metamorphosis Most groups with this form of metamorphosis are aquatic Nymphs and adults somewhat different in appearance Nymphs have gills Adults are terrestrial with tracheal systems Complete Metamorphosis Young stages may be very different from adults Early stages are called larvae Pupal stage between larval and adult stage Wings develop internally until pupalstage Mouthparts change type in some orders 16
Complete Metamorphosis Types of Larvae eggs adult larval stages pupa (in cocoon) Types of Pupae Very common misconception Common Orders of Insects Order Common Name Metamorphosis Mouthparts Wings Common Orders of Insects Order Common Name Metamorphosis Mouthparts Wings Orthoptera grasshoppers, gradual chewing 2 pair crickets Mantodea mantids gradual chewing 2 pair Dermaptera earwigs gradual chewing 2 pair Coleoptera beetles, weevils complete chewing 2 pair Neuroptera lacewings complete chewing 2 pair Hymenoptera bees, ants, complete chewing 2 pair wasps Isoptera termites gradual chewing 2 pair Hemiptera bugs, hoppers, gradual piercing-sucking 2 pair aphids, scales Lepidoptera moths, complete chewing/ 2 pair butterflies siphoning Diptera flies complete chewing/ 1 pair piercing-sucking 17
Insect Orders: Orthoptera Insect Orders: Mantodea Grasshoppers, crickets, katydids Chewing mouthparts; adults and nymphs damaging Gradual metamorphosis Forewings are elongate, narrow, and somewhat thickened; hindwings are membranous with extensive folded area. Hind legs often enlarged for jumping Immature stages (nymphs) resemble wingless adults Praying mantids Chewing mouthparts; adults and nymphs damaging Gradual metamorphosis Forewings are elongate, narrow, and somewhat thickened; hindwings are membranous with extensive folded area. Raptorial front legs Immature stages (nymphs) resemble wingless adults Insect Orders: Hemiptera Insect Orders: Homoptera (now joined into Hemiptera) True bugs Piercing-sucking mouthparts Gradual metamorphosis Half-wing - front wing is thick at base, membranous at tip Antennae of five or more segments, long and conspicuous or short and concealed Immature insects are similar to the adult but wings are incomplete or absent Aphids, leafhoppers, cicadas, whiteflies, scales Piercing-sucking mouthparts Gradual metamorphosis Adults are winged or wingless; when present, hind wing is shorter than the front wing Immature stages usually similar to adult but wingless Serious pests of cultivated plants and sometimes vectors of plant diseases Insect Orders: Thysanoptera Insect Orders: Neuroptera Thrips Modified piercing-sucking mouthparts; adults and nymphs damaging Gradual metamorphosis Wings are like sticks with long hairs Immature stages (nymphs) resemble wingless adults Some disease vector relationships Lacewings, antlions, snakeflies, mantispids, dobsonflies, dustywings, alderflies Insect predators; many are aquatic Two pairs of similar-sized wings Chewing mouthparts Complete metamorphosis 18
Insect Orders: Coleoptera Insect Orders: Lepidoptera Beetles and weevils Chewing mouthparts on adults and immatures Complete metamorphosis Front wings (elytra) hardened, shell-like Adults usually have noticeable antennae Larvae have head capsules, usually three pairs of legs on the thorax and no legs on the abdomen Butterflies and moths Chewing mouthparts on larvae, siphoning on adults Complete metamorphosis Wings covered with colored scales Adults usually have noticeable antennae Larvae have head capsules, usually three pairs of legs on the thorax and prolegs on the abdomen Insect Orders: Hymenoptera Insect Orders: Diptera Sawflies, bees, wasps & ants Chewing mouthparts on larvae & adults Complete metamorphosis Two pair of membranous wings on adults Adults usually have noticeable antennae Many adults bear stingers Larvae in two main forms caterpillar-like or grubs with head capsules Flies & Mosquitoes Larvae with chewing mouthparts, adults with piercing-sucking or sponging mouthparts Complete metamorphosis Adults with one pair of membranous wings Larvae with no legs on thorax or abdomen Rather soft-bodied or slightly hardened adults Exercise 2 Identification Keys Sort your insects to order level Dichotomous keys Picture keys Word keys Combinations 19
Picture Keys Picture Keys Word Keys Must be read with utmost attention to detail Mark choices with pencil or sticky notes Dichotomous Keys Most combine word couplets and figures when needed to clarify descriptions Key: An arrangement or listing of the significant characteristics of a group of organisms, used as a guide for taxonomic identification Taxonomic Key: Taxonomic keys are like a flow chart, consisting of a series of decision point at which the user has to compare specimens to descriptions, figures or pictures to decide what path to follow 20
Taxonomic Key: Taxonomic keys are like a flow chart, consisting of a series of decision points at which the user has to compare specimens to descriptions, figures or pictures to decide what path to follow Dichotomous Key: A key constructed so that at each decision point there are only two options Wings are present Yes No The path does not necessarily follow lines of relation or phylogeny Front wings thickened Yes No More than 6 legs Yes No That s all, folks! Erwin Duke Elsner Small Fruit Educator MSU Extension 520 W. Front Street elsner@anr.msu.edu 231-922-4822 21