When you want to identify an insect the first step is to find out in which Order it is classified. For this you can use a dichotomous key. A dichotomous key is a tool that uses paired statements or questions to guide you to the solution.
To use the key it will be necessary to have a good hand lens and you should be familiar with the terminology used for the different parts of an insect body. To use the key, start at the top and compare statements 1a and 1b. Select the statement that describes your insect specimen and continue with the number indicated on the right click the number to jump to the next statement. Identification keys are a good starting point, but you should realize that there are hundred thousands of insect species in this world and among them there is a lot of variation.
The keys cannot cover all this variation. When you have reached a solution, always double check the result by reading a detailed description of the insect Order.
The dorsal surface of the prothorax extends backwards over the abdomen; the hind-legs enlarged and modified for jumping; insect looks grasshopper-like in general appearance. The wings elytra meet in the centre-line sometimes they are fused together and without veins note that the elytra may have longitudinal grooves or striae but these should not be confused with veins. The wings have only one forked vein; antennae are relatively long; small insect usually less than 5 mm long.
The thorax has a pair of club-shaped structures halteres lying just behind the wings these halteres may be hidden by body hairs and other structures. The forewings are partly or entirely horny or leathery and form stiffened covers for the membranous hindwings.
Both pairs of wings are membranous flexible and used for flying sometimes the wings are feather-like rather than membranous or their membranous nature may be obscured by a covering of hairs, scales or waxy powder. The forewings overlap at least a little in the centre-line and usually with many veins present.
The forewings elytra meet in the centre-line and have no veins note that the elytra may have longitudinal grooves or striae but these should not be confused with veins.
The hind-legs are enlarged and modified for jumping; insect looks like a grasshopper in general appearance. The hind-legs are not modified for jumping and are usually similar in thickness to the middle-legs; insect is not grasshopper-like. The prothorax is much larger than the head; cerci nearly always many-segmented and fairly prominent. The wings are very narrow without veins and fringed with long hairs feather-like ; tarsi are 1- or 2-segmented; small slender insect often found in flowers.
The wings broader with veins present; if wings are fringed with long hairs then tarsi are comprised of more than 2 segments the wing veins of some insects may be much reduced and hardly visible or partly obscured by hairs, scales or waxy powder. Wings and much of the body covered with white waxy powder; tiny insect usually less than mm long.
When at rest the wings are held roof-wise over the body; the mouth-parts have jaws mandibles and are designed for biting. The wings are usually transparent wings without scales but often hairy ; the mouth-parts are not forming a coiled proboscis.
The forewings have many cross-veins making a network pattern; the abdomen has 2 or 3 long thread-like terminal appendages. The forewings show relatively few cross-veins; the abdomen is usually without or with only very short terminal appendages cerci.
The wings are not noticeably hairy but wings may be fringed with hairs or tiny surface hairs may be seen if wings are inspected under a microscope or strong hand-lens. The wings are not noticeably hairy but tiny hairs may be seen if the wings are observed under a microscope or with a strong hand-lens. The front of the head is extended downwards to form a beak-like structure with jaws mandibles at its tip.Insects or Insecta from Latin insectum are hexapod invertebrates and the largest group within the arthropod phylum.
Definitions and circumscriptions vary; usually, insects comprise a class within the Arthropoda. As used here, the term Insecta is synonymous with Ectognatha. Insects have a chitinous exoskeletona three-part body headthorax and abdomenthree pairs of jointed legscompound eyes and one pair of antennae. Insects are the most diverse group of animals; they include more than a million described species and represent more than half of all known living organisms.
Nearly all insects hatch from eggs. Insect growth is constrained by the inelastic exoskeleton and development involves a series of molts. The immature stages often differ from the adults in structure, habit and habitat, and can include a passive pupal stage in those groups that undergo four-stage metamorphosis. Insects that undergo three-stage metamorphosis lack a pupal stage and adults develop through a series of nymphal stages. The most diverse insect groups appear to have coevolved with flowering plants.
Adult insects typically move about by walking, flying, or sometimes swimming. Insects are the only invertebrates to have evolved flight, and all flying insects derive from one common ancestor.
Many insects spend at least part of their lives under water, with larval adaptations that include gillsand some adult insects are aquatic and have adaptations for swimming. Some species, such as water stridersare capable of walking on the surface of water. Insects are mostly solitary, but some, such as certain beesants and termitesare social and live in large, well-organized colonies.
Major Insect Orders Mini-Book
Some insects, such as earwigsshow maternal care, guarding their eggs and young. Insects can communicate with each other in a variety of ways. Male moths can sense the pheromones of female moths over great distances. Other species communicate with sounds: crickets stridulateor rub their wings together, to attract a mate and repel other males. Lampyrid beetles communicate with light.
Humans regard certain insects as pestsand attempt to control them using insecticidesand a host of other techniques. Some insects damage crops by feeding on sap, leaves, fruits, or wood. Some species are parasiticand may vector diseases.
Some insects perform complex ecological roles; blow-fliesfor example, help consume carrion but also spread diseases. Insect pollinators are essential to the life cycle of many flowering plant species on which most organisms, including humans, are at least partly dependent; without them, the terrestrial portion of the biosphere would be devastated. Silkworms produce silk and honey bees produce honey and both have been domesticated by humans.
The word "insect" comes from the Latin word insectummeaning "with a notched or divided body", or literally "cut into", from the neuter singular perfect passive participle of insectare"to cut into, to cut up", from in - "into" and secare "to cut";  because insects appear "cut into" three sections.The following 30 pages are in this category, out of 30 total. This list may not reflect recent changes learn more.
From Wikipedia, the free encyclopedia. Insect orders. Archaeognatha jumping bristletails. Thysanura Zygentoma silverfish, firebrats. Ephemeroptera mayflies. Odonata dragonflies, damselflies. Plecoptera stoneflies Dermaptera earwigs Embioptera webspinners Phasmatodea stick and leaf insects Notoptera ice-crawlers, gladiators Orthoptera crickets, wetas, grasshoppers, locusts Zoraptera angel insects. Blattodea cockroaches, termites Mantodea mantises. Psocodea barklice, lice Thysanoptera thrips Hemiptera cicadas, aphids, true bugs.
Hymenoptera sawflies, wasps, ants, bees. Strepsiptera twisted-winged parasites Coleoptera beetles. Raphidioptera snakeflies Megaloptera alderflies, dobsonflies, fishflies Neuroptera net-winged insects: lacewings, mantidflies, antlions. Trichoptera caddisflies Lepidoptera moths, butterflies. Four most speciose orders are marked in bold Italic are paraphyletic groups Based on Sasaki et al.
Extinct incertae sedis families and genera are marked in italic. The main article for this category is Insect orders. Subcategories This category has the following 3 subcategories, out of 3 total.
Pages in category "Insect orders" The following 30 pages are in this category, out of 30 total.
A Archaeognatha. B Blattodea.Insects class Insecta have segmented bodies, jointed legs, and external skeletons. Insects are distinguished from other arthropods by their body, which is divided into three major regions: 1 the head, which bears the mouthparts, eyes, and a pair of antennae, 2 the three-segmented thorax, which usually has three pairs of legs in adults and usually one or two pairs of wings, and 3 the many-segmented abdomen, which contains the digestive, excretory, and reproductive organs.
This is an alphabetical list of significant insects grouped by order. List of insects. Info Print Print. Table Of Contents. Submit Feedback. Thank you for your feedback. Introduction ants, bees, and wasps order Hymenoptera beetles and weevils order Coleoptera butterflies and moths order Lepidoptera caddisflies order Trichoptera cockroaches order Blattodea crickets, grasshoppers, and katydids order Orthoptera diplurans order Diplura dragonflies and damselflies order Odonata earwigs order Dermaptera fleas order Siphonaptera flies order Diptera gladiator bugs order Mantophasmatodea hemipterans order Hemiptera homopterans order Homoptera ice bugs order Grylloblatodea lacewings or neuropterans order Neuroptera lice order Phthiraptera mantids order Mantodea mayflies order Ephemoptera megalopterans order Megaloptera psocids order Psocoptera scorpionflies order Mecoptera stoneflies order Plecoptera strepsipterans order Strepsiptera termites order Isoptera thrips order Thysanoptera true bugs order Heteroptera walkingsticks order Phasmida webspinners order Embioptera apterygote subclass Apterygota.
See Article History. Sahara desert ant genus Cataglyphis. Colorado potato beetle Leptinotarsa decemlineata. June beetles genus Phyllophaga. Jerusalem crickets subfamily Stenopelmatinae. March flies family Bibionidae. San Jose scale Quadraspidiotus perniciosus.
Learn More in these related Britannica articles:. Insectclass Insecta or Hexapodaany member of the largest class of the phylum Arthropoda, which is itself the largest of the animal phyla. Insects have segmented bodies, jointed legs, and external skeletons exoskeletons. Insects are distinguished from other arthropods by their body, which is divided into three major regions:…. Arthropodany member of the phylum Arthropoda, the largest phylum in the animal kingdom, which includes such familiar forms as lobsters, crabs, spiders, mites, insects, centipedes, and millipedes.
About 84 percent of all known species of animals are members of this phylum. Arthropods are represented in every habitat on Earth…. Antfamily Formicidaeany of approximately 10, species of insects order Hymenoptera that are social in habit and live together in organized colonies. Ants occur worldwide but are especially common in hot climates.
They range in size from about 2 to 25 mm about 0. Their colour…. History at your fingertips. Sign up here to see what happened On This Dayevery day in your inbox!There are more insects than any other organisms on Earth.
Insects are in the Phylum Arthopoda, identified by their jointed legs, segmented bodies, and exoskeletons. All insects have these characteristics, but other characteristics further define Class Insecta: three pairs of jointed legs, bodies that have three segments, one pair of antennae, and usually two pairs of wings some groups have one pair or none. What are identifying characteristics of an insect? What are the different major orders of insects and how can you tell them apart?
I can identify insects and the characteristics that place them in the six most common insect orders. Ask students to make observations about the insects…. How they are alike? How they are different? Download Lesson Plan. Download PowerPoint 1.
Insects play an important role in our lives and are the most common organisms on Earth. There are some insects that can harm you or damage crops, but the majority of insects are good for the environment. They help us to pollinate our plants, are an integral part of food webs, make products that we can use, and recycle wastes.
They are easy to observe and catch in any type of environment. There are over thirty identified orders within the Class Insecta.
This activity familiarizes students with the six most populous orders of insects by producing Mini-Books with the name of each order on a separate page, examples of common insects in that order, a picture, identifying characteristics, and an interesting fact. Students will create Mini-Books highlighting the primary characteristics of the six major orders of insects.
YouTube Video. Written Directions. Students share their Mini-Books with others in the classroom and check books for completeness before turning into the teacher for a final grade. Students are challenged to find an example of an insect from each of the six most populous orders. Presentation of their insects could be through a traditional insect collection of mounted insects or another option is to take a picture of an insect from each order, which is less destructive to the environment.
For a great resource for teaching students about insects and shows several methods of collecting insects, visit Purdue University's website for 4-H. Moisset, Beatrix. Iowa State University Entomology, 6 Sept. Insect Identification Org, 3 Apr. National Wildlife Federation, n. University of Kentucky, n.Study With Me: Insect Orders #1
Email us about this lesson plan. Explore This Park. Overall Rating Excellent. Focus Questions: What are identifying characteristics of an insect?Disclaimer : Dedicated naturalists volunteer their time and resources here to provide this service. We strive to provide accurate information, but we are mostly just amateurs attempting to make sense of a diverse natural world.
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Probably many first time visitors to Bugguide would benefit from an overview of all the orders of insects with some explanation of their main identifying characteristics.
It follows the one created by Arnett 1pages for beginners. Insects with: 1. Four large wings, covered by scales: Order Lepidoptera - Butterflies and Moths 2.
Four wings; the first pair thickened or hardened. Similar to Coleoptera but with short wing covers and with abdominal forceps: Order Dermaptera - Earwigs Caution: If there are no forceps, it is probably a beetle, Family: Staphylinidae 4.
Resembling Coleoptera, but the posterior half of the front wings somewhat translucent or thinner and with veins. Four wings, front ones somewhat thickened. Two pairs of membranous wings similar in size and texture. Four membranous wings, front wings larger than hind ones. Large head. Only one pair of wings; membranous, with conspicuous veins. No abdominal filaments: Order Diptera — Flies No wings, usually with scales and long abdominal filaments. Note: some members of other orders are also wingless but body shape resembles that of winged members of the same order, e.
Long antennae segments Order Notoptera — Rock crawlers American Insects. Pages: I will be very grateful for any suggestions, corrections, comments, etc. I have never been very good with keys and I am very ignorant about entire orders of insects; so I am sure that many of you have some good ideas that could help me improve this article. Guide to Insect Orders. Hi Beatriz, Thank you for your efforts. The guide is just what I need for a quick reference.
I am re-learning this topic some 50 years since my college courses and am starting at a very basic level. The link under Order Dictyoptera - Mantids does not seem to point to anything useful. I am glad you caught that. The taxonomy was changed a year after I wrote this article. This led me to finding three other problems.
I wish I had known this sooner. I hope that there are no more changes at the higher taxonomic levels.
Since this thread popped up Mayflies can have a median filament, but stoneflies won't.Familiarity with the twenty-nine insect orders is the key to identifying and understanding insects.
In this introduction, we have described the insect orders beginning with the most primitive wingless insects, and ending with the insect groups that have undergone the greatest evolutionary change.
Most insect order names end in pterawhich comes from the Greek word pteronmeaning wing. The silverfish and firebrats are found in the order Thysanura. They are wingless insects often found in people's attics, and have a lifespan of several years. There are about species worldwide. Diplurans are the most primitive insect species, with no eyes or wings. They have the unusual ability among insects to regenerate body parts.
Insect groups (Orders)
There are over members of the order Diplura in the world. Another very primitive group, the proturans have no eyes, no antennae, and no wings. They are uncommon, with perhaps less than species known. The order Collembola includes the springtails, primitive insects without wings. There are approximately 2, species of Collembola worldwide. The mayflies of order Ephemeroptera are short-lived, and undergo incomplete metamorphosis. The larvae are aquatic, feeding on algae and other plant life.
Entomologists have described about 2, species worldwide. The order Odonata includes dragonflies and damselflieswhich undergo incomplete metamorphosis. They are predators of other insects, even in their immature stage. There are about 5, species in the order Odonata. The stoneflies of order Plecoptera are aquatic and undergo incomplete metamorphosis. The nymphs live under rocks in well flowing streams. Adults are usually seen on the ground along stream and river banks. There are roughly 3, species in this group.
Sometimes referred to as "living fossils," the insects of the order Grylloblatodea have changed little from their ancient ancestors. This order is the smallest of all the insect orders, with perhaps only 25 known species living today. Grylloblatodea live at elevations above ft.
These are familiar insects grasshoppers, locusts, katydids, and crickets and one of the largest orders of herbivorous insects. Many species in the order Orthoptera can produce and detect sounds. Approximately 20, species exist in this group. The order Phasmida are masters of camouflage, the stick and leaf insects. They undergo incomplete metamorphosis and feed on leaves.
There are some 3, insects in this group, but only a small fraction of this number is leaf insects. Stick insects are the longest insects in the world. This order contains the earwigs, an easily recognized insect that often has pincers at the end of the abdomen.
Many earwigs are scavengers, eating both plant and animal matter. The order Dermaptera includes less than 2, species. The order Embioptera is another ancient order with few species, perhaps only worldwide.