Entomology
| Entomology | |||||||
|---|---|---|---|---|---|---|---|
| Type | Life Science | ||||||
| Category | Study | ||||||
| Description | Students will be asked to identify insects and selected immature insects by indicated taxonomy (order, subclass, or family), answer questions about insects, and use or construct a dichotomous key. All specimens will be representatives of insects found in the Contiguous United States. | ||||||
| Event Information | |||||||
| Participants | 2 | ||||||
| Allowed Resources |
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| Approx. Time | 50 minutes | ||||||
| History | |||||||
| First Appearance | 1991 | ||||||
| Latest Appearance | 2026 | ||||||
| Rotates | Yes | ||||||
| Forum Threads | |||||||
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| Question Marathon Threads | |||||||
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| Official Resources | |||||||
| Division B Website | www | ||||||
| Division C Website | www | ||||||
| Division B Results | |||||||
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| Division C Results | |||||||
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Entomology is a Division B and Division C life science event in which competitors must be able to identify insects and other arthropods from 26 orders, 2 subclasses, and 113 families. On most tests, questions about behavior, structure, human impact, economic consequences, management, and any characteristics of certain insects may be asked. This event is similar to the old event Don't Bug Me which was renamed for the 2007 season.
The 2025 Official Insect List is located on soinc.org. The 2026 list is not yet posted on the website but can be found in the rules. Note that the list is the same for both Division B and Division C. For information about the insects on the official list, see Entomology/Entomology Insect List. However, some tournaments (including regional and state tournaments) may use a modified insect list which may have added local insects or a shorter range of testable species and/or families.
Up to two competitors are allowed to compete from a given team, and they usually get around 50 minutes to complete the exam. The competition is commonly run as stations: students travel to one station/section at a time for a certain period of time. When the time for that station is complete, students will move to the next station and repeat the process until 50 minutes are up. Some tournaments (especially online tournaments) opt to use one complete test rather than stations, where students have the entire 50 minutes to answer questions in any order they choose. Students are allowed to bring a binder of 2" or smaller (as measured by internal rings), a commercially published field guide, a hand lens or magnifying glass, writing utensils, and a copy of the insect list provided.
Entomology rotates with Invasive Species, Herpetology, Ornithology, and Forestry every 2 years for both Division B and Division C. It was an event for 2014 and 2015, rotating out for Invasive Species in 2016. However, the event returned for the 2025 and 2026 seasons.
What is an insect?
An insect is an invertebrate with several distinguishing characteristics. These characteristics, which are also outlined in the table below, include: segmented bodies with paired, many jointed legs; 3 major body sections; 6 legs; and 2 antennae.
The name "insect" comes from Latin insectum: in and seco ("cut up"). Similarly, "entomology" derives from Greek entomos ("cut in pieces"). This is a reference to how insects appear to be cut into three parts: the head, thorax, and abdomen.
"Hexapod" refers to "six legs", "arthropod" refers to "jointed leg". Both names are Greek-derived.
Insects are also the only arthropods to have wings; however this does not mean all insects have wings. Some (like Zygentoma and Archaeognatha) never evolved wings, while others secondarily lost their wings after evolving from a winged ancestor.
Insect Taxonomy
All insects are classified as members of the following taxonomic groups:
- Kingdom: Animalia
- Phylum: Arthropoda
- Subphylum: Hexapoda
- Class: Insecta
- Subphylum: Hexapoda
- Phylum: Arthropoda
In addition, Hexapoda contains classes/orders Collembola, Protura, and Diplura. These may be considered orders belonging to class Entognata or considered separate classes themselves (in particular Diplura may be closer to Insecta than it is to the other Entognaths) but this is still being debated.
The 2025 Entomology List also contains family Ixodidae, also known as hardbacked ticks, which belong to order Ixodida (ticks) within subclass Acari (mites and ticks). These are of class Arachnida (arachnids) in subphylum Chelicerata (which includes sea spiders and horseshoe crabs as well).
This table outlines major characteristics members of each group are required to possess.
| Level | Name of Rank | Characteristics Required |
|---|---|---|
| Kingdom | Animalia | Heterotrophic; Eukaryotic; Multicellular; No cell wall, no chloroplasts; Motile (able to move, opposite of sessile); Sense Organs. |
| Phylum | Arthropoda | Chitinous exoskeleton that must be shed during growth (molting); Jointed paired appendages (legs and antennae); Segmented bodies that are arranged into regions, called tagmata (e.g., head, thorax, abdomen); Bilateral symmetry; Ventral nervous system; Open, dorsal circulatory system; |
| Clade | Mandibulata | Have modified appendages (mandibles) flanking the mouth and used as jaws; |
| Subphylum | Hexapoda | 3 pairs of legs (6 total) that are located on the thorax |
| Class | Insecta | Head, thorax, abdomen; 3 pairs of legs (one on each thoracic segment); One pair of antennae on head; 1-2 pairs of wings in most; Pair of compound eyes in most, along with 1-3 simple eyes; |
General Tips for identifying Insects
A very important part of this event is learning how to quickly identify the order and family of a given insect. The following is a list of tips for discerning the order/family of an insect.
- Color is generally not a good way to ID and differentiate insects.
- For orders such as Hymenoptera, Diptera, and Lepidoptera, wing venation is very important in identification to family level.
- Know each major order's defining traits. Below are the four most diverse orders of insects and their defining characteristics:
- Diptera: Only one pair of functional wings, second pair of wings modified into halteres (small club-shaped structures used as gyroscopes)
- Hymenoptera: Forewings usually larger than hind wings, hooked together by hamuli
- Coleoptera: Forewings modified into hardened elytra, which serve as protective covers for hind wings
- Lepidoptera: Two large pairs of wings, hooked together by a frenulum
A good way to learn identification is to practice! This means practicing with BugBo (the Discord bot dedicated to helping you learn), looking at Google images, using flashcards, or going outside to look at bugs in the real world.
Insect Development
- Morphogenesis: All changes that involve growth, molting, and maturation
Molting
- Triggered by hormones released when an insect's growth reaches the physical limits of its exoskeleton
- Marks the end of one instar or growth stage, and the start of another
- When it becomes sexually mature, an inset is known as an imago or adult. At this point, molting stops and energy for growth is channeled into production of eggs or sperm.
- An insect cannot survive without the protection and support of its exoskeleton, so a new, larger one must be constructed inside the old one
Here is a summary of the processes involved in insect molting:
- Step 1: Apolysis -- separation of old exoskeleton from epidermis
- Step 2: Secretion of inactive molting fluid by epidermis
- Step 3: Production of cuticulin layer for new exoskeleton
- Step 4: Activation of molting fluid
- Step 5: Digestion and absorption of old endocuticle
- Step 6: Epidermis secretes new procuticle
- Step 7: Ecdysis -- shedding the old exo- and epicuticle
- Step 8: Expansion of new integument
- Step 9: Tanning -- sclerotization of new exocuticle
Types of Metamorphosis
Not all insects develop in the same way. Types of metamorphosis are grouped based on the number of stages required to reach sexual maturity. The table below explains the different types of metamorphosis and gives example groups.
| Metamorphosis Type (alternate name) | Description | Wing Type | Example Orders |
|---|---|---|---|
| Ametabola (no metamorphosis) | Young resembles the adult, but is smaller. Development involves increasing the insect's size by going through successive molts. | Apterogyte (adults like immature without wings) | Protura, Diplura, Collembola, Archaeognatha, Zygentoma |
| Hemimetabola (incomplete metamorphosis) | Developmental stages include egg, nymph, adult | Exopterygote (wings develop externally on the nymph body) | Ephemeroptera, Odonata, Blattodea, Mantodea, Notoptera, Dermaptera, Plecoptera, Orthoptera, Phasmatodea, Psocodea, Hemiptera, Thysanoptera |
| Holometabola (complete metamorphosis) | Developmental stages include egg, larva, pupa, adult | Endopterygote (wings develop inside of body in immature insects and not visible until adult emerges from pupa) | Megaloptera, Neuroptera, Coleoptera, Strepsiptera, Mecoptera, Raphidioptera, Siphonaptera, Diptera, Trichoptera, Lepidoptera, Hymenoptera |
Larvae Appearance
Most larvae can be divided into five basic groups based on their appearance.
Pupa Appearance
Pupae can be grouped into one of three categories based on physical appearance.
Insect Behavior
In this event, it is important to understand the basics of insect behavior. While this is not a major portion of the event, a basic knowledge is necessary. For example, you should know about social interactions between insects, and have a rudimentary understanding of the ways in which insects communicate with one another.
Social Insects
Some groups of insects, such as termites and bees, live together in a common nest or colony. Social behavior can vary greatly from group to group. Different classifications of social behavior are outlined below.
| Classification Name | Common Nest Site | Cooperative Brood Care | Reproductive Castes | Generation Overlap |
|---|---|---|---|---|
| Solitary | No | No | No | No |
| Communal or Subsocial | Yes | No | No | No |
| Quasisocial | Yes | Yes | No | No |
| Semisocial | Yes | Yes | Yes | No |
| Eusocial | Yes | Yes | Yes | Yes |
Definitions for each classification outlined in the table are below:
- Solitary: Not sharing a nest or providing care for offspring
- Communal: Members of the same generation use the same composite nest site without cooperating in brood care
- Subsocial: Adults provide some kind of parental care for their offspring
- Quasisocial: Members of the same generation use the same composite nest site and also cooperate in brood care
- Semisocial: Cooperative brood care within a composite nest is provided by a worker caste that is more or less sterile
- Eusocial: Cooperative brood care within a composite nest is provided by a worker caste that is more or less sterile and lives long enough to assist the parents. In order to be considered eusocial, an insect group must possess all four of the following characteristics:
- Share a common nest site
- Individuals of the same species cooperate in caring for the young
- Reproductive division of labor - sterile (or less fecund) individuals work for the benefit of a few reproductive individuals
- Overlap of generations - offspring contribute to colony labor while their parents are still alive
Advantages and Disadvantages of Living in Groups
Advantages:
- Can accomplish feats that are impossible for solo insects
- Construction of huge nest sites
- Widespread foraging for food
- Constant vigilance against predation or parasitism
Disadvantages:
- Large colonies are especially vulnerable to the spread of contagious pathogens
- Nest sites may be exploited by "social parasites" who steal food or attack the brood
- Individuals must compete with each other for space and resources (such as food)
Links for Information About Specific Social Insects
Insect Communication
- Communication: An action or condition on the part of one organism that alters the behavior of another organism in an adaptive way.
- Insects communicate with one another for a variety of reasons, including:
- Recognition of kin or nestmates
- Locating or identifying a member of the opposite sex
- Facilitation of courtship and mating flasher
- Giving directions for location of food or other resources
- Regulating spatial distribution of individuals -- aggregation or dispersal
- Establishing and maintaining a territory
- Warning of danger; setting off an alarm
- Advertising one's presence or location
- Expressing threat or submission (agonistic behaviors)
- Deception / mimicry
- Types of communication include tactile, visual, acoustic, and chemical communication.
Tactile Communication
Many insects with poor vision and sound perception use physical contact as an important means of communication. Examples of insects that use tactile communication are listed below.
- Meloidae: courtship begins with a series of antennal taps by the male on each side of the female's body. She signals her receptivity by lifting her wing covers (elytra) and allowing him to climb on her back. But to complete his quest, the male must continue tapping, alternating from side to side at just the right frequency until the female is stimulated to extend her genitalia and begin mating.
- Formicidae and Isoptera: Antennal Tapping- It is unclear what type of information is exchanged during antennal tapping, but it certainly involves nestmate recognition and leads to exchange of food through trophallaxis.
- Tandem Running: A "follow-the-leader" behavior in which the tapping informs the leader that she has not lost her disciple. If tapping stops, the leader instinctively turns around and searches in ever-widening circles until she re-establishes contact with the follower.
- Honeybees: "Dance Language" For more information about the dance language of honeybees, please see this page
- Gyrinidae: Tactile cues generated by ripples on the water surface allow the beetles to constantly monitor the location of dozens of other nearby whirligigs. Thanks to this tactile communication system, the whirligigs can swim rapidly in circles, avoid bumping into other members of their own species, and still detect the presence of nearby predators or prey.
- Membracidae (certain species): Produce vibrations in the tissue of their host plant that can be felt by all other treehoppers on the same plant. The signals apparently work as an alarm system, and in some species, they may be used by nymphs to elicit protective maternal behavior. Substrate vibrations can be a particularly effective system of communication for small insects who cannot generate an acoustic signal loud enough to be heard more than few inches away.
Some benefits to tactile communication include:
- Instantaneous Feedback
- Localized Area
- Individual Recipient
- Effective in the dark (e. g. caves, wood galleries)
Some limiting factors to tactile communication include:
- Not effective over distance
- Insects must stay in direct contact
- Message must be repeated to each recipient
- Vibration signals can be intercepted by predators
Chemical Communication
Insects seem to rely more on chemical signals more than any other form of communication. They use their senses of taste and smell to detect the presence of chemical compounds in the air. Chemoreceptorscan be found anywhere on the body, but are most commonly found on the feet, antennae, palps, and ovipositor. These signals are divided into two main groups: semiochemicals and infochemicals.
Semiochemicals can be divided into two groups based on who "sends" a message and who "receives" it:
- Pheromones are chemical signals that carry information from one individual to another member of the same species. These include sex attractants, trail marking compounds, alarm substances, and many other intraspecific messages.
- Allelochemicals are signals that travel from one animal to some member of a different species. These include defensive signals such as repellents, compounds used to locate suitable host plants, and a vast array of other substances that regulate interspecific behaviors.
- Allelochemicals can be further subdivided into three groups based on who "benefits" from the message:
- Allomones benefit the sender such as a repellent, or defensive compound (e. g. cyanide) that deters predation.
- Kairomones benefit the receiver- such as an odor that a parasite uses to find its host.
- Synomones benefit both sender and receiver. Examples include plant volatiles that attract insect pollinators.
Some benefits of chemical communication include:
- Not limited by environmental barriers
- Effective over distances and around corners
- Effective either day or night
- Longer lasting than visual or auditory signals
- Metabolically "inexpensive" because only small quantities are needed
Some limiting factors of chemical communication include:
- Low information content (presence/absence)
- Not effective in an upwind direction
- Can attract predators or parasites
Acoustic Communication
Most insects detect sound with a tympanic membrane in the abdomen (e.g. grasshoppers and moths) or in the tibiae of the front legs (e.g. crickets and katydids). Mosquitoes have antennal hairs that resonate to certain frequencies of sound. But sound vibrations can also travel through solid objects, and some insects (e.g. some species of ants, bees, termites, and treehoppers) can sense substrate vibrations with mechanoreceptors (chordotonal organs) in their legs. Since these signals are "felt" rather than "heard", they are usually regarded as a form of tactile communication.
Some benefits of acoustic communication include:
- Not limited by environmental barriers
- Effective over distances and around corners
- Highly variable, fast change- high information content
- Some limiting factors of acoustic communication include:
- May reveal location of sender to a potential predator
- Less effective in "noisy" environments (e.g. seashore)
- May be metabolically "expensive" to produce
- Attenuation- intensity falls rapidly with distance from source (cube-root function)
Visual Communication
Many insects communicate with visual signals. These visual signals usually fall into one of two groups: active or passive signals.
Passive signals, such as eyespots and color patterns can serve as a form of "free advertising". The colorful wings of a butterfly, for example, are a "billboard" publicizing its species identity. Individual insects incur little or no metabolic cost for displaying these messages because they are an integral part of the integument. It may be prudent to hide these signals from a potential predator, so some insects have a way to conceal their message when necessary. The red admiral butterfly, for example, has bright, distinctive markings on the upper wing surface and drab, protective coloration on the underside.
Active signals, like body movements and light flashes, are more costly to produce, but they can be withheld from use at inappropriate times. They may also have a higher information content because signal frequency, duration, or periodicity may convey additional meaning. In fireflies, for example, pulses of light are used in a courtship dialogue between a male (usually flying) and a female (usually perched in the vegetation). Each species has a unique flash pattern and response time.
Some benefits of visual communication include:
- Effective over long distances
- Can be used while moving
- Fast- speed of light
- Effective in all directions (independent of wind)
- Passive signals require no expenditure of energy
Some limiting factors of visual communication include:
- Requires a clear line of sight
- Visual signals may be intercepted by predators
- Only effective in daylight (in fireflies, only at night)
- Active signals may be metabolically "expensive" to produce
Insect Ecology
Relating to insect ecology in this event, you will most likely be asked if an insect is a herbivore/carnivore/decomposer and what it feeds on. It is also important to have a basic understanding of parasitism, as many insects are parasites.
Trophic Levels
- All insects are consumers. They may be found in all levels of a food chain except the first.
- For more information about tropic levels and basic ecology, please visit this page.
Herbivores
- Phytophagy/phytophagous: Relating to plant feeding
- Monophagous: An insect that restricts itself to a single host species
- Oligophagous: An insect with a slightly broader host range
- Polyphagous: Equipped with "broad-spectrum" detoxification enzymes that can overcome a wide range of plant defenses
- Feeding Guild: Within a feeding guild, all species compete directly with each other for exactly the same resource. Between members of different guilds, competition is usually less direct and less severe.
Insects that eat plants generally use visual or olfactory cues to locate a host plant. Visual cues can include the vertical silhouette of a tree or certain shapes/colors that insects associate with "food". Odor cues are plant volatiles such as the saponins in alfalfa, the mustard oils in crucifers, or the terpenes in conifers.
Carnivores
- Zoophagy: A term for all insects that: catch and kill other insects (or other animals) as food, eat living or decomposing animal flesh, or feed by sucking blood
- Predators: zoophagous insects that kill and eat numerous prey individuals in the course of their growth and development. Usually much larger than their prey
Parasitism
- Parasite: an organism that lives in or on another organism (its host) and benefits by deriving nutrients at the host's expense. Usually much smaller than their host, and may complete their development on the body of a single host individual.
- A "true" parasite does not kill its host, but it may spread disease pathogens or cause other disability such as skin irritation, intestinal blockage, organ failure, or allergic reactions.
- Endoparasites: Live inside the host's body
- Ectoparasites: Live in the host's nest or on the surface of its body
- Hematophagy: Blood feeding- a common practice among insects that parasitize vertebrate animals (Siphonaptera, Phthiraptera)
- Parasitoid: An insect that lives in or on the body of a single host individual during their larval stage but become free-living as adults. These insects do not fit the classical definition of a "parasite" because they feed on the internal organs and tissues of the host individual and eventually kill it.
- Hyperparasites: parasites (or parasitoids) of another parasitoid species.
- Autoparasites: species in which the females feed on males to obtain a nutritional advantage.
- Brood Parasites: insects that live in the nests of social insects and feed on the juveniles.
- Social Parasites: insects that steal food or other resources from the nests of social insects.
Decomposers
- Saprophages: Insects that eat the dead bodies of plants and animals. These insects are an important part of the biosphere because they help recycle dead organic matter
- Within the ranks of saprophagous insects, entomologists recognize several major groups:
- Those that feed on dead or dying plant tissues
- Include a wide variety of soil- and wood-dwelling species that shred leaves or tunnel in woody tissues. They accelerate decay by increasing the surface area exposed to weathering and the action of other decomposers. They are largely responsible for creating a layer of humus that often covers the soil. This layer serves as an incubator for the fungi, bacteria, and other microorganisms that release carbon, nitrogen, and mineral elements for uptake by living plants.
- Those that feed on dead animals (carrion)
- Include numerous beetles, fly larvae (maggots), wasps, ants, mites, and others. Each species colonizes the dead body for only a limited period of time but collectively, they rapidly consume and/or bury the decaying flesh. Blow flies, usually the first to arrive on a carcass, are also the first to complete development and depart. Other species follow over time in a relatively predictable sequence as the body decomposes.
- Those that feed on the feces of other animals
- Many species of manure flies and dung beetles are attracted to the odor of animal excrement. Adults lay their eggs on fresh feces and larvae feed on the organic matter in these waste products. Many dung-feeders exhibit distinct preferences for particular types of manure: the species associated with horse manure, for example, may be quite different from those found on the same farm in cattle manure.
- Those that feed on dead or dying plant tissues
- In addition to their role as decomposers, some saprophagic insects also serve as pollinators for plants like skunk cabbage and wild ginger. These plants produce drab colored, foul smelling flowers that attract the attention of blow flies or carrion beetles. The insects crawl around in the flowers looking for food and unwittingly pick up pollen.
Survival Strategies
Insects owe their success throughout geologic time to a variety of adaptations and survival strategies.
Relating to anatomy, insects have the following adaptations:
- An exoskeleton
- Small size
- Flight
- Reproductive potential
- Metamorphosis
- Adaptability
Relating to behavior, insects have the following adaptations:
- Migration
- Diapause
- Cold-Hardiness
- Parthenogenesis
- Polymorphism
Anatomical Defenses
The Exoskeleton
An insect's supporting skeleton is located on the outside of its body. This exoskeleton gives shape and support to the body's soft tissues, protects from attack or injury, minimizes the loss of bodily fluids in both arid and freshwater environments, and gives a mechanical advantage for strength and agility in movement. As a "suit of armor", the exoskeleton can resist both physical and chemical attack. It is covered by an impervious layer of wax that prevents desiccation. Much of the exoskeleton is fabricated from chitin, a polysaccharide that binds with various protein molecules to form a body wall that may be as flexible and elastic as rubber or as hard and rigid as some metals. Freedom of movement is ensured by membranes and joints in the exoskeleton. Muscles that attach directly to the body wall combine maximum strength with near-optimum mechanical advantage (leverage). The result is an ant, for example, that can lift up to 50 times its own body weight.
Small Size
Many insects are between 2 and 20mm in length. For an animal with an exoskeleton, small size is a distinct advantage. If insects were as large as cows or elephants, their exoskeleton would have to be proportionately thicker to support the additional mass of body tissue. A thicker exoskeleton would also be heavier and more cumbersome. Even the simplest movements would require a larger muscle volume and consume more energy.
Small size also minimizes the amount of resources insects need for survival and reproduction. For example, a crumb can be a large meal, a dewdrop can be a large drink, and a pebble can provide shade. Many insects may live on a single plant or animal for its entire life and never exhaust its food supply.
Lastly, small size is an advantage to insects that must avoid predation. They can hide in the cracks of a rock, beneath the bark of a tree, behind the petal of a flower, or under a blade of grass. The exoskeleton is hard enough for them to burrow between individual grains of sand, yet flexible enough to let them squeeze through the tiniest of cracks. Small size, together with adaptations in body shape and coloration, gives many species the ability to blend so well with their environment that they become virtually undetectable.
Flight
Insects are the only invertebrates that can fly. Judging from the fossil record, they acquired this ability about 300 million years ago - nearly 100 million years before the advent of the first flying reptiles. Flight is a highly effect mode of transportation and escape from predators. It allowed insects populations to expand more quickly into new habitats.
Reproductive Potential
- High Fecundity: Females produce large amounts of eggs
- High Fertility: A majority of the eggs hatch
High fecundity, high fertility, and a short life cycle allow insects to produce large numbers of offspring. Since most insects die before they ever have an opportunity to reproduce, a high reproductive potential is the species' best chance for survival. Many adaptations help maximize this potential. Most females, for example, can store sperm for months or years within the spermatheca, a special region of the reproductive system. A single mating can supply a female with enough sperm to fertilize all the eggs she will produce in her lifetime. An unbalanced sex ratio, where females outnumber males, is another way to maximize reproductive potential. Since most insects are not monogamous, a few males can supply sperm for a large number of females. And finally, there are many species (e.g. aphids, scale insects, thrips, and midges) where males are entirely absent - all members of the population are female and contribute offspring through a process of asexual reproduction.
Metamorphosis
- Metamorphosis: The significant developmental changes experienced by insects as they grown from immatures to adults. Can include physical, biochemical, and/or behavioral alterations that promote survival, dispersal, and reproduction of the species.
More primitive insects typically experience changes gradually as they mature. Since this transformation process is slow and does not include all body tissues (incomplete metamorphosis) the immatures and adults share many characteristics - they often live in similar habitats and feed on similar types of food.
Advanced insects, however, undergo complete metamorphosis. In these cases, a larva is adapted for feeding and growth. It assimilates energy reserves which, in some cases, will sustain the insect for the rest of its life. When fully grown, a larva molts into a transitional stage, called the pupa, and begins a period of massive internal and external reorganization. Body organs and tissues encoded by larval DNA are disassembled and rebuilt according to a second DNA blueprint that had been repressed during larval life. An adult insect (imago) eventually emerges from within the pupal exoskeleton bearing little or no resemblance to its larval form. Its primary function is dispersal and reproduction.
Metamorphosis gives the more advanced insects an advantage because through natural selection, larval form and function can be optimized for growth and feeding without compromising adaptations of the adult for dispersal and reproduction. Each stage of the life cycle is entirely free to adapt to its own ecological role. In some cases, this means that immatures and adults may consume different types of food, exploit different environmental resources, and even occupy different habitats.
Behavioral Strategies
Migration
- Migration: A period of directional movement that carries an insect beyond the range of their local habitat. This survival strategy has at least six potential advantages:
- Escape from natural enemies
- Find more favorable growing conditions
- Reduce competitions or relieve overcrowding
- Locate new/unoccupied habitats
- Disperse to alternate host plants
- Reassort the gene pool to minimize inbreeding
Although most insects migrate by flying, a few species (chinch bugs, Mormon crickets, and armyworms, for example) travel on the ground. Migration by flight is often aided by prevailing winds. Once airborne, small insects may be lifted by thermal convection and carried hundreds of miles on frontal air masses. Even wingless individuals may be carried aloft by "ballooning" on silk threads or blowing off tall vegetation. Larger insects, like dragonflies and monarch butterflies, may control the direction of their migratory flights, but most smaller insects are carried wherever the wind blows them.
Migration is usually a distinct phase in the life cycle, almost always occurring before the onset of reproductive maturity. Migrants are innately programmed to move; they are not distracted by food or mates. Once the migratory urge is satisfied, the insect is generally in a physiological state to continue development or commence reproduction. Migration can be a very risky venture: in some species more than 90% of a population may die in transit. Despite such high mortality rates, the reproductive success of individuals who survive the trek apparently makes the gamble worthwhile for the species as a whole.
Diapause
- Diapause: A period of hormone-induce "dormancy". Characterized by reduction in oxygen consumption, metabolic rate, and physical activity. Feeding and growth are generally interrupted while the individual subsists on stored food reserves. Diapause typically occurs during the egg stage in some species, during a nymphal or larval instar in other species, or during the pupal stage in still other species. Even adults may enter a "reproductive diapause" which causes a significant delay in the onset of sexual maturity.
In temperate climates, many species enter diapause in the fall as an overwintering adaptation. Other species, however, have a summer diapause that helps them survive the dryness and/or heat. In either case, the onset of diapause is triggered by an environmental cue that precedes the adverse weather conditions (short daylengths in fall, for example). Diapause continues, even under apparently favorable conditions, until it is "broken" (terminated) by other environmental cues, such as long day lengths or exposure to a substantial period of low temperature.
Diapause is not always correlated with adverse environmental conditions. It can also regulate development within a population to ensure optimal timing of emergence or temporal synchrony with environmental resources. Female rabbit fleas, for example, have an obligate adult diapause that is broken only by feeding on the blood of a pregnant host rabbit. By the time the baby rabbits are old enough to be weaned, the flea's offspring will be mature and ready to accompany the rabbits when they leave the nest. In this ecological relationship, diapause is an adaptation that keeps the flea population from exceeding the carrying capacity of its host.
Cold-Hardiness
Since insects are poikilotherms (cold-blooded animals), their body temperature is usually similar to that of the air (or water) around them. Species that live in cold mountain streams (like mayfly naiads) or on the surface of ice and snow (like grylloblattids) are adapted for activity at low temperatures. Most other insects, however, slow down as the temperature falls.
They reach a dormant state, called torpor or quiescence, when they get very cold. Physiologically, many insects prepare for winter weather by producing "antifreeze" compounds (such as glycerol, sorbitol, or trehalose) in their hemolymph and body tissues. High concentrations of these compounds can increase cold-tolerance by lowering the freezing point of body fluids and preventing the formation of ice crystals that would cause internal injury. In species that manage to survive in arctic and alpine environments, the overwintering stage may undergo extensive dehydration - any ice crystals that do form will be too small to cause cellular damage.
Unlike diapause , a period of quiescence lasts only as long as the weather is cold. When temperatures rise, quiescent insects resume normal activity - at least until the next cold front arrives.
Insect External Anatomy
In this event, questions about general anatomy can come in two basic forms: diagrams to label, or arrows pointing to a specific structure on an insect. For the latter, competitors are generally asked to identify the structure, and possibly name its function.
Head
The head is the anterior oval-shaped body region that that houses the brain, a mouth opening, mouthparts used for ingestion of food, and major sense organs (including antennae, compound eyes, and ocelli). The surface of the head is divided into regions (sclerites) by a pattern of shallow grooves (sutures).
- Vertex: The uppermost sclerite (dorsal surface) of the head capsule
- Coronal Suture: runs along the midline of the vertex and splits into two frontal sutures as it extends downward across the front of the head capsule
- Frons: The triangular sclerite that lies between these frontal sutures
- Epistomal Suture: A deep groove that separates the base of the frons from the clypeus
- Clypeus: A rectangular sclerite on the lower front margin of the head capsule
- Genae: Lateral sclerites that lie behind the frontal sutures on each side of the head
See [1] for more information and an interactive diagram of the head that includes all features listed above.
Eyes
Insects generally have two types of eyes, simple and compound eyes. For more information about insect eyes, please visit this website
Simple Eyes (Ocelli)
Most insects have three simple eyes, also known as ocelli, located on the upper front part of the head. Several insects lack ocelli or only have two. The term ocellus (the singular form of ocelli) is derived from the Latin oculus (eye), and literally means "little eye".
There are two distinct types of ocelli: dorsal ocelli (or simply "ocelli"), and lateral ocelli (or stemmata).
Dorsal ocelli are commonly found in adults and in the immature stages (nymphs) of many hemimetabolous species. They are not independent visual organs and never occur in species that lack compound eyes. Whenever present, dorsal ocelli appear as two or three small, convex swellings on the dorsal or facial regions of the head. They differ from compound eyes in having only a single corneal lens covering an array of several dozen rhabdom-like sensory rods. These simple eyes do not form an image or perceive objects in the environment, but they are sensitive to a wide range of wavelengths, react to the polarization of light, and respond quickly to changes in light intensity. No exact function has been clearly established, but many physiologists believe they act as an "iris mechanism" -- adjusting the sensitivity of the compound eyes to different levels of light intensity. Dorsal ocelli are generally larger and more prominent in flying insects, such as bees, dragonflies, wasps, and locusts. In these insects, they are typically found in groups of three. Two lateral ocelli are directed to the left and right of the head, while a central ocellus is directed frontally. Some insects, such as ants and cockroaches, only possess two ocelli. In these cases, the median ocellus is absent, and both lateral ocelli are present.
Stemmata are the sole visual organs possessed by the larvae of insects that experience complete metamorphism, and certain adult orders that exhibit various types of metamorphism (ex: Collembola, Thysanura, Siphonaptera, and Strepsiptera). Stemmata always occur laterally on the head, and vary in number from one to six on each side. Structurally, they are similar to dorsal ocelli but often have a crystalline cone under the cornea and fewer sensory rods. Larvae use these simple eyes to sense light intensity, detect outlines of nearby objects, and even track the movements of predators or prey.
Compound Eyes
Compound eyes are the most commonly found visual organ of insects. They are situated on the upper portion of an insect's head. As suggested by their name, they are composed of many similar facets, called ommatidia. The number of ommatidia varies considerably from species to species: some worker ants have fewer than six while some dragonflies may have more than 25,000. For more information about the composition of an individual ommatidia, please see the link specified earlier in this section.
Antennae
The antennae are usually located on the front of the head below the simple eyes. They can be used to sense motion, orientation, odor, sound, humidity, chemicals in the air.
Antennae are divided into three basic parts: the scape: the basal segment that articulates with the head capsule; the pedicel: the second antennal segment; and the flagellum: all the remaining "segments" (individually called flagellomeres)
See [2] for pictures. The table found at this link is definitely something to include in a cheat sheet.
| Name | Examples |
|---|---|
| Setaceous: Bristle-like | Dragonflies |
| Filiform: Thread-like | Ground beetles and cockroaches |
| Moniliform: Bead-like | Termites |
| Serrate: Sawtoothed | Click beetles |
| Clavate: Gradually clubbed | Carrion beetles |
| Capitate: Abruptly clubbed | Butterflies |
| Pectinate: Comb-like | Fire-colored beetles and male glow-worms |
| Plumose: Brush-like | Mosquitoes, some moths |
| Geniculate: Elbowed | Weevils, ants |
| Aristate: pouch-like with lateral bristle | Houseflies |
| Flabellate/Flabeliform: Fan-like | Some beetles, some wasps, some moths |
| Lamellate: Nested Plates | Scarab beetles |
| Stylate: Stylus-like | Robber flies; Bee flies |
Mouthparts
The mouth parts of an insect are located on the ventral or anterior part of the head. The mouth part structures typically present include:
- Labrum: a cover which may be loosely referred to as the upper lip.
- (Jaw-like) Mandibles: hard, powerful cutting jaws
- (Jaw-like) Maxillae: 'pincers' which are less powerful than the mandibles. They are used to steady and manipulate the food. They have a five segmented palp which is sensory and often concerned with taste.
- Labium: the lower cover, often referred to as the lower lip. It actually represents the fused pair of ancestral second maxillae. They have a three segmented palp which is also sensory.
- Hypopharynx: a tongue-like structure in the floor of the mouth. The salivary glands discharge saliva through it.
Mouth parts are generally divided into groups, as explained below. Two major groups include chewing (or mandibulate) and sucking (or haustellate). Haustellate mouthparts can be further divided into piercing-sucking, sponging, and siphoning.
Chewing (Mandibulate)
These forms of mouthparts are among the most common in insects, which are used for biting and grinding solid foods. Examples of chewing insects include dragonflies, grasshoppers and beetles. Some insects do not have chewing mouthparts as adults but do as larvae, such as moths and butterflies.
Sucking (Haustellate)
Insects with sucking mouth parts have parts like a beak which is called the proboscis through which liquid is sucked.
Thorax
This is the middle section of the body and is divided into 3 segments called the prothorax, mesothorax, and metathorax. Each segment bears a pair of legs, and the mesothorax and metathorax usually bear a pair of wings if the insect is not wingless. Each of the thoracic segments bear 4 groups of sclerites, or platelike areas. These are the notum (dorsally), pleuron (there's one on each side), and sternum (ventrally). These segments are then divided into even smaller segments.
Wings
The wings are located dorsolaterally (they're near the top) on the mesothroax and/or the metathorax. The muscles that move wings are attached to the walls of the thorax most of the time. Insect wings vary in number, size, shape, texture, venation, and in position held at rest making them a great assist in identification. Most insect wings are membranous, though some are thickened or leathery. Some are covered in hair and others in scales. Most insects fold their wings over the abdomen at rest, but others hold them vertically over the body or hold them outstretched. Here's a picture of wing venation:
General Venation
See bottom of http://www.cals.ncsu.edu/course/ent425/tutorial/wings.html for more.
Legs
Most insects have three pairs of legs. Each leg contains five structural components (segments) that articulate with one another by means of hinge joints. These five components are known as the coxa, the trochanter, the femur, the tibia, and the tarsus.
Different insects' legs are modified for different tasks. This table outlines the major types of leg adaptations found in insects.
Abdomen
The abdomen houses the insect's digestive tract, reproductive organs, and external appendages. It typically consists of 11 segments, but the last segment is usually represented by appendages only. Many insects have fewer abdominal segments because of fusing of some insects. Each abdominal segment generally contains 2 sclerites (or hardened body wall plate), a dorsal tergum and ventral sternum. The terga usually extend down the sides of most segments and overlap the sterna. Most insects lack appendages on the abdomen other than at the posterior end. This appendages may be lacking or drawn into the body and hidden. When these terminal appendages are present, they usually consist of a pair of cerci, a median dorsal epiproct (appendage above anus), a pair of paraprocts (pair of lobes located below and on each side of anus), and genitalia. The anal opening is on the posterior end of the abdomen, right under the epiproct. The sexes in many groups can be identified by the genitalia at the end of the abdomen.
| Structure Name | Function | Description of Structure | Example Taxons |
|---|---|---|---|
| Cerci | Sensory, defense, courtship, or vestigial | Appendages attached to the end of an insect's abdomen, can take on a variety of shapes including pincers and threadlike filaments | Orthoptera, Blattodea, Dermaptera, Zygentoma, Archaeognatha, Odonata, etc |
| Median Cadual Filament | Defense, courtship, folding wings | A thread-like projection arising from the center of the last abdominal segment (between the cerci) | "Primitive" orders such as Diplura, Thysanura, Ephemeroptera |
| Pincers | Defense, courtship, folding wings | Modified cerci; heavily sclerotized and forceps-like | Dermaptera |
| Cornicles | Produce substances that repel predators or elicit care-giving behavior by symbiotic ants | paired secretory structures located dorsally on the abdomen of aphids | Aphididae |
| Abdominal Prolegs | Locomotion | Fleshy, found in larvae | Mostly Lepidoptera, also in Mecoptera and some Hymenoptera |
| Ovipositor | Lay eggs, reach otherwise impossible areas to deposit eggs via drilling or piercing; in the case of Aculeata also act as stingers | Tubelike; thin | Female Orthoptera, Hymenoptera, Diptera, etc |
| Stinger | Defend against predators, immobilize prey | Modified ovipositor, sharp, with or without barbs | Found only in females of aculeate Hymenoptera (ants, bees, and predatory wasps) |
| Petiole | Attach abdomen to thorax | Thin, narrow "waist" consisting of 1-2 segments | Certain Apocrita (ants, bees, wasps) insects |
| Abdominal Gills | Respiration | Ephemeroptera-paired gills are located along the sides of each abdominal segment; Odonata- the gills are attached to the end of the abdomen | Found in aquatic nymphs (naiads) of Ephemeroptera and Odonata |
| Furcula | "Jumping", springing locomotion | The "springtail" jumping organ found in Collembola on the ventral side of the fifth abdominal segment. A clasp (the tenaculum) on the third abdominal segment holds the springtail in its "cocked" position. | Collembola |
| Collophore | Maintains homeostasis by regulating absorption of water from the environment | Fleshy, peg-like structure found on ventral side of first abdominal segment | Collembola |
Insect Identification (2026 Orders Only)
For more detailed information about each taxon (both orders and families), please visit the Entomology/Entomology Insect List page.
| Order Name (nickname) | Metamorphosis | Characteristics | Notes |
|---|---|---|---|
| Protura (Telsontails, Proturans) | None | conical head, piercing mouthparts, lacks eyes and wingless, 12 segments in abdomen,
0.6-1.5mm |
No longer considered an insect but its own separate order within Hexapoda; sometimes grouped with Collembola and Diplura into group Entognatha (characterized by internal mouthparts as opposed to the external mouthparts insects have); this is heavily debated today |
| Collembola (Springtails, Snow Fleas) | None | wingless, long bodies, 4-6 abdominal segments, multicolored, tube protrudes from abdomen, microscopic | No longer considered an insect but its own separate order within Hexapoda; sometimes grouped with Protura and Diplura into group Entognatha (characterized by internal mouthparts as opposed to the external mouthparts insects have); this is heavily debated today |
| Diplura (Diplurans) | None | 1-segmented tarsi, chewing mouthparts, 2 cerci on head | No longer considered an insect but its own separate order within Hexapoda; sometimes grouped with Protura and Collembola into group Entognatha (characterized by internal mouthparts as opposed to the external mouthparts insects have); this is heavily debated today |
| Archaeognatha (Bristletails) | None | spindle shaped, flat bodies with 3 long, bristly tail-like appendages (median/middle filament considerably longer than cerci) | Formerly grouped with Zygentoma into outdated order Thysanura |
| Zygentona (Silverfish, Firebrats) | None | spindle shaped, flat bodies with 3 long, bristly tail-like appendages of subequal length, silvery scales | Formerly grouped with Archaeognatha into outdated order Thysanura |
| Ephemeroptera (Mayflies) | Simple | one or two pairs of large triangular wings, short flexible antennae, large compound eyes, three ocelli, nonfunctional mouthparts, two or three long cerci | |
| Odonata (Dragonflies, Damselflies) | Simple | two pairs of elongate membranous wings, compound eyes large, abdomen long and slender, antennae very short | |
| Blattodea (Cockroaches, Termites) | Simple | Cockroaches: flattened oval bodies, long laid back antennae
Termites: small, soft-bodies, usually pale-colored, antennae generally short and thread- or bead-like; eusocial |
Formerly split into Blattodea (cockroaches) and Isoptera (termites); molecular and genetic evidence now suggests termites evolved from a lineage of cockroaches effectively making termites cockroaches |
| Mantodea (Mantids) | Simple | triangular heads, bulging eyes, forelegs adapted for catching and grabbing prey | |
| Notoptera (Ice Crawlers) | Simple | small wingless insects with long antennae and elongated cerci | Divided into Mantophasmatidae (gladiators/rock crawlers) and Grylloblattidae (ice crawlers)
NOT included on the 2026 list but was on 2025 list |
| Embioptera (Webspinners) | Simple | long, narrow, flexible bodies, short legs, kidney-shaped compound eyes, chewing mouthparts, no ocelli, long threadlike antennae,
only males have wings |
New for 2026 list |
| Dermaptera (Earwigs) | Simple | slender flattened bodies, large pincers at end | |
| Plecoptera (Stoneflies) | Simple | 4 membranous wings, elongate, flattened, cerci present, long antennae, mouthparts chewing | |
| Orthoptera (Grasshoppers, Crickets) | Simple | usually 2 pairs of wings, antennae many-segmented, cerci present, FW is long, narrow, and many veined, strong hind legs adapted for jumping | |
| Phasmatodea (Walkingsticks) | Simple | some have cylindrical sticklike shapes while others are leaflike and flattened; all are generally adapted to resemble vegetation
Chewing mouthparts with long slender legs and antennae |
|
| Psocodea (Book/Bark Lice) | Simple | small, with chwing mandibles, a swollen forehead, large compound eyes, three ocelli, soft and segmented abdomen | Formerly split into Mallophaga (chewing lice) and Anoplura (sucking lice) |
| Hemiptera (True Bugs) | Simple | piercing-sucking mouthparts, folded under body when not in use
forewings either partially hardened: thickened at base and membranous at tip (most Heteroptera) or entirely membranous (other Hemiptera) forewings held flat on the back with ends overlapping (Heteroptera) or roofwise over body (other Hemiptera) 4-5 segments on antennae, leg tarsi have 2-3 segments |
Formerly divided into Hemiptera/Heteroptera ("true bugs") and Homoptera (cicadas, treehoppers, froghoppers/spittlebugs, leafhoppers, aphids); studies show that Homoptera was paraphyletic and thus was added to Hemiptera |
| Thysanoptera (Thrips) | Simple | slender bodies, short antennae, short legs, feathery/fringed wings, asymmetrical mouthparts | |
| Megaloptera (Dobsonflies) | Complete | pleated region on hindwings, strong mandibles, large compound eyes, large subequal wings | Formerly placed in Neuroptera (lacewings, antlions) |
| Neuroptera (Lacewings, Antlions) | Complete | FW and HW almost same size, four membranous wings, wings held rooflike over body at rest, wings with many veins, antennae long, cerci absent, mouthparts chewing | Formerly included Megaloptera (dobsonflies) |
| Coleoptera (Beetles) | Complete | FW horny or leathery, FWs meet in straight line on back, HW membranous and are usually longer than FW, wings rarely absent or reduced, antennae usually with 11 segments (sometimes with 8-10), antennae variable in form, chewing mouthparts | |
| Strepsiptera (Twisted-wing Parasites) | Complete | males: forewings modified into club shaped halteres for gyroscopic information, fan-shaped hindwings with strongly reduced venation, flabellate antennae, few dozen cuticle-separated eyelets on each eye
females: neotenic in form, with no wings, legs, or eyes |
NOT included on the 2026 list but was on 2025 list |
| Mecoptera (Scorpionflies) | Complete | slender, soft bodies; long legs and elongated, snout-like heads | |
| Raphidioptera (Snakeflies) | Complete | elongated prothorax, heavily schlerotized long and flattened head, strong mouthparts, large compound eyes | |
| Siphonaptera (Fleas) | Complete | laterally flattened abdomens, tough skin, enlarged coxae, mouthparts with 3 piercing stylets for blood sucking | |
| Diptera (True Flies) | Complete | one pair of membranous wings, HWs modified into knoblike projections called halteres for flight stabilization, short antennae | |
| Trichoptera (Caddisflies) | Complete | shaped or colored like certain moths, antennae long and threadlike, antennae usually long as body or longer, HW a little shorter than FW | |
| Lepidoptera (Moths, Butterflies) | Complete | 4 membranous wings covered in scales, usually have coiled proboscis or highly reduced mouthparts as adults | |
| Hymenoptera (Bees, Ants, Wasps) | Complete | wings are sometimes present, FW a little larger than HW, FW and HW usually joined together with small hooks called hamuli, antennae usually fairly long, females of many species have ovipositors adapted to lay eggs in hosts or hard-to-reach places, sometimes modified into a stinger | |
| Ixodidae (Hardbacked Ticks) | None | external parasites with a scutum (hard dorsal covering), piercing mouthparts adapted for feeding on blood, adults have eight legs | Not an insect, not a hexapod, but an arachnid; included here because of its placement on the National Entomology List (2025) |
Dichotomous Keys
On the tests, you may be asked to create a simple dichotomous key for identification of various insects. To create, just remember some simple tips:
There should be one less number of steps than number of insects you're including in the key.
You want to start off by dividing the insects into groups. If they do not have the insects already identified for you, then quickly identify them. For example, if they give you a house fly, a mantid, a dragonfly, and a mosquito, you'll divide them like this:
1. Two pairs of wings...................................go to 2
1. One pair of wings.....................................go to 3
Keep them very basic at first, then eventually divide them into more specific groups.
For example, you could then divide the two groups into colors, or whatever is most convenient.
Keep dividing the groups until you end up with the final step(since there are four insects in this case, there will be three steps) leading to the final insect being identified.
Again, having knowledge of the distinguishing characteristics of each family/specimen would be very helpful.
Human Impact
A very important aspect of this event is learning about how insects impact humans, the environment, and the world. Usually tests will feature stations with questions regarding identification and human/environmental/economic impact. Some insects are very prominent pests, such as certain species of Coleoptera, while others are highly beneficial, such as butterflies or bees that pollinate.
Beneficial Insects
Insect populations can have a positive impact on humans in a variety of different ways. They can be sources of food, decompose organic matter, pollinate important crops, manufacture products such as silk and honey, recycle carbon/nitrogen/other essential nutrients, and control populations of harmful invertebrates including other insects. Some are also valuable organisms to study for scientific and technological advances. Others have medical and therapeutic value.
Harmful Insects
In addition to having a positive effect on humans, insects can be very harmful. For example, some insects damage crops/trees and destroy products such as wood and paper. Many termites can destroy entire homes. Some (such as ants) can bite or sting, and many vector diseases. Others are household pests and parasites.
Disease Vectors
As stated above, many insects serve as vectors for diseases. Arbovirus is a term used to refer to a group of viruses that are transmitted by arthropod vectors. It is an acronym (ARthropod-BOrne virus). Haematophagous insects feed on blood at some stage of their life, and in the process of doing so, can transmit several diseases. Other insects (such as many flies) can also cause flystrike where females lay eggs inside living flesh for the hatched larvae to feed on. Still other insects (like cockroaches) carry pathogens on their bodies which may cause food contamination or allergies.
| Name of Insect | Disease |
|---|---|
| Siphonaptera (fleas) | Plague |
| Culicidae (mosquitoes) | Malaria, filarisis*, arboviral encephalitides, dengue fever, Rift Valley fever, West Nile encephalitis viral infection |
| Calliphoridae (blow flies) | Dysentery rabbit haemorrhagic disease, flystrike, salmonellosis |
*Only female mosquitoes of the genus Anopheles transmit malaria and filarisis
Pest Management
Whether they are household, agricultural, or public health pests, many species of insects have to be controlled to minimize the damage to humans, livestock, crops, property, and wildlife. This can be done via a variety of means, whether mechanical, cultural, chemical, or biological. Traditionally, conventional pesticides were used; while effective short-term they led to many other problems such as environmental degradation, loss of wildlife, pesticide resistance, and toxic effects on humans. Chemical pest control is still the main form of control today, but these risks led to more studies on biological or mechanical control.
Mechanical: physically removing insects from the area, using traps
Cultural: employing techniques such as tilling, crop rotation, weeding
Chemical: using chemicals to kill or deter pests
Genetic: genetically modifying plants to have resistance against insects or modifying insects/sterilizing them
Biological: release natural enemies (predators or parasites) to control the pest population
Insect Conservation
As a result of human action, the diversity of insect species has been rapidly declining whether it is because of climate change, pesticide use, light pollution, habitat loss, or invasive species, while notable pest populations are increasing as they adapt to urban environments. One way you can combat this is reducing pesticide use, turning artificial lights off when not used, using warm colored lights that are more directed, and planting native plants to support local insect populations.
Insects in Human Culture
Insects have appeared in art, music, and literature since ancient times, holding significant religious and cultural symbolism from antiquity to modern-day. For example, scarabs in Ancient Egypt represented Ra, since they way they rolled dung was a metaphor for how Ra would roll the sun across the sky. Aesop's fables includes the story of the Ant and the Grasshopper. Even today many insects are recognized for their role in human culture.
Below is a list of all US state insects:
| State | Common name | Scientific name |
|---|---|---|
| Alabama | Monarch butterfly (state insect) | Danaus plexippus |
| Queen honeybee (state agricultural insect) | Apis mellifera | |
| Eastern tiger swallowtail (state butterfly, mascot) | Papilio glaucus | |
| Alaska | Four-spotted skimmer dragonfly | Libellula quadrimaculata |
| Arizona | Two-tailed swallowtail (state butterfly) | Papilio multicaudata |
| Arkansas | European honeybee (state insect) | Apis mellifera |
| Diana fritillary butterfly (state butterfly) | Speyeria diana | |
| California | California dogface butterfly (state butterfly) | Zerene eurydice |
| Colorado | Colorado hairstreak | Hypaurotis crysalus |
| Connecticut | European mantis | Mantis religiosa |
| Delaware | Ladybug (state insect) | Coccinellidae |
| Eastern tiger swallowtail (state butterfly) | Papilio glaucus | |
| Stonefly (state macroinvertebrate) | Plecoptera | |
| Florida | Zebra longwing (state butterfly) | Helioconius charitonius |
| Georgia | European honeybee (state insect) | Apis mellifera |
| Eastern tiger swallowtail (state butterfly) | Papilio glaucus | |
| Hawaii | Kamehameha butterfly | Vanessa tameamea |
| Idaho | Monarch butterfly | Danaus plexippus |
| Illinois | Monarch butterfly | Danaus plexippus |
| Indiana | Say's firefly | Pyractomena angulata |
| Kansas | European honeybee | Apis mellifera |
| Kentucky | European honeybee (state agricultural insect) | Apis mellifera |
| Viceroy butterfly (state butterfly) | Limenitis archippus | |
| Louisiana | European honeybee (state insect) | Apis mellifera |
| Gulf fritillary (state butterfly) | Dione vanillae | |
| Maine | European honeybee (state insect) | Apis mellifera |
| Pink-edged sulphur (state butterfly) | Colias interior | |
| Maryland | Baltimore checkerspot butterfly | Euphydryas phaeton |
| Massachusetts | Ladybug | Coccinellidae |
| Minnesota | Monarch butterfly (state butterfly) | Danaus plexippus |
| Rusty patched bumblebee (state bee) | Bombus affinis | |
| Mississippi | European honeybee (state insect) | Apis mellifera |
| Spicebush swallowtail (state butterfly) | Papilio troilus | |
| Missouri | European honeybee | Apis mellifera |
| Montana | Mourning cloak butterfly (state butterfly) | Nymphalis antiopa |
| Nebraska | European honeybee | Apis mellifera |
| Nevada | Vivid dancer damselfly | Argia vivida |
| New Hampshire | Ladybug (state insect) | Coccinellidae |
| Karner blue butterfly (state butterfly) | Plebejus melissa samuelis | |
| New Jersey | European honeybee (state insect) | Apis mellifera |
| Black swallowtail (state butterfly) | Papilio polyxenes | |
| New Mexico | Tarantula hawk wasp (state insect) | Pepsis grossa |
| Sandia hairstreak (state butterfly) | Callophrys mcfarlandi | |
| New York | Nine-spotted ladybug | Coccinella novemnotata |
| North Carolina | European honeybee (state insect) | Apis mellifera |
| Eastern tiger swallowtail (state butterfly) | Papilio glaucus | |
| North Dakota | Convergent lady beetle | Hippodamia convergens |
| Ohio | Ladybug | Coccinellidae |
| Oklahoma | European honeybee (state insect) | Apis mellifera |
| Black swallowtail (state butterfly) | Papilio polyxenes | |
| Oregon | Oregon swallowtail | Papilio oregonius |
| Pennsylvania | Pennsylvania firefly | Photuris pennsylvanica |
| Rhode Island | American burying beetle | Nicrophorus americanus |
| South Carolina | Carolina mantis (state insect) | Stagmomantis carolina |
| Eastern tiger swallowtail (state butterfly) | Papilio glaucus | |
| South Dakota | European honeybee | Apis mellifera |
| Tennessee | Common eastern firefly (state insect) | Photinus pyralis |
| Ladybug (state insect) | Coccinellidae | |
| European honeybee (state agricultural insect) | Apis mellifera | |
| Zebra swallowtail (state butterfly) | Eurytides marcellus | |
| Texas | Monarch butterfly | Danaus plexippus |
| Utah | European honeybee | Apis mellifera |
| Vermont | European honeybee (state insect) | Apis mellifera |
| Monarch butterfly (state butterfly) | Danaus plexippus | |
| Virginia | Eastern tiger swallowtail | Papilio glaucus |
| Washington | Green darner dragonfly | Anax junius |
| West Virginia | European honeybee (state insect) | Apis mellifera |
| Monarch butterfly (state butterfly) | Danaus plexippus | |
| Wisconsin | European honeybee | Apis mellifera |
| Wyoming | Sheridan's green hairstreak | Callophrys sheridanii |
Some states have multiple designated insects or different categories. Iowa and Michigan lack a designated state insect. Note that more than half of these insects are not native to North America (especially the western honeybee which was imported from the Old World for honey production/apiculture).
Binder Checklist
*NOTE* As with other ID events in the past, Entomology used to be a cheatsheet (one double-sided, 8.5 x 11 inches page of information) and field guide event. However, in recent years these events have shifted to binder events, meaning that for the 2025 season teams are allowed to have a 2" binder (as measured by internal rings) containing any information from any source, as well as one commercially published field guide and a hand lens. Note that for station-based competitions, nothing besides the official list may be outside of the binder.
Here is a binder checklist that was useful in the past: Make sure you have the following information in your binder or known by memory: Definitely necessary:
- Insect identification guide and sheets
- Nymph identification sheets
- Insect pictures (obviously)
- Insect characteristics sheets
- Human impact information
- Basic insect information such as anatomy
Optional:
- Entomology glossary (to be on the safe side)
- Note Sheets (for quick finding if they have a section where you must answer questions about insects not already identified) for the following:
- Vectors
- Record-winning insects (largest, smallest, fastest fliers, most deadly, etc.)
- Historical info. (safe side, horrible test making at state had at least five questions on this subject)
- Invasive species
Cheat Sheet Suggestions
In this event, there are a variety of ways which one can use to structure their cheat sheet. Three basic methods are listed below. The bottom line is to find a method that works the best for you, and practice with it. You may want to add more information for certain groups (that are easier to identify, such as Mecoptera or Neuroptera families), and more pictures for others (that are hard to identify, such as Lepidoptera families).
Information you should definitely save space for on your cheat sheet that is not taxon specific includes:
- A table with different types of leg adaptations (adaptation name and picture, can be found above)
- A table with different types of antennae adaptations (adaptation name and picture, can be found above)
- A table with different types of wing adaptations (adaptation name and picture, can be found above)
- Insect taxonomy (see section of this page on Insect Taxonomy, you will want to include the characteristics required for each group)
- Anatomy diagrams- usually works to find a good one for the head, mouthparts, leg, wing, and whole body.
- Wing Venation- General info and a diagram
Method 1- Information and Pictures
This method involves having information about all of the families on one side of the sheet, and information about orders and other miscellaneous stuff on the other side. Information about all families and orders can be found on the Entomology/Entomology Insect List page. The identification tables at the end of each section are definitely a good idea for identification, along with pictures.
| Aspect | Pro | Con |
|---|---|---|
| Location of Information During Test | Can be very easy to located information if you know the location of everything well | If you don't have a good idea of where everything is, it can be very hard to locate it in time |
| Amount of Information | Will include lots of information | Can sometimes be hard to fit everything, be careful about adding irrelevant information; |
| Identification | Because it includes both pics and descriptions, you will be much more confident in your identification of a specimen | Some pictures can be misleading, for insects that mimic each other. (Example: Sesiidae, resembles a Hymenoptera |
Method 2- Pictures Only
This method involves putting only pictures to aid with identification on your cheat sheet. For example, you may choose to designate a small space on the back side of the sheet for a few pictures of each family, and on the front put a few pictures for each order (along with some anatomy diagrams, because there would be space left over). The main issue with this method is that you will have to look in your field guide for the answers to questions such as "What does this insect eat?" or "Where does this insect live?" etc.
| Aspect | Pro | Con |
|---|---|---|
| Location of Information During Test | You are allowed to annotate the field guide, so feel free to add as much information about each group that you have room for. | You will need to use your field guide to locate information during the test. Tabbing for at least the orders is a good idea, and you can put page numbers on the sheet for the families. |
| Amount of Information | Won't include any useless information- Identification is the most important aspect of this event | Will include no information other than pictures of appearance |
| Identification | A VERY good method for those who struggle with ID'ing insects, you will have more room to add more pictures for each group. Therefore, you will have more confidence in your identification of a specimen. | If you're not organized about the location of your pictures, you could accidentally place one under the wrong group |
Method 3- Information Only
This method involves only adding information about each taxon to your cheat sheet, without pictures. For example, under Corixidae you may put the information found here, in either format. (See top of page for more info). The main issue with this method is since it does not involve adding pictures, you will have to become very confident with identification. Please note that the field guide is generally not a good way to ID insects if you are using the Audubon, because the pictures are arranged by appearance and not by taxonomic group. Flipping through the book to find the correct order or family will waste time during the test.
| Aspect | Pro | Con |
|---|---|---|
| Location of Information During Test | Will be easy if you know the cheat sheet well and work out a color coding scheme. | Might be somewhat harder since there aren't pictures to give you a guide, but isn't a huge issue if you become familiar with layout. |
| Amount of Information | Will include tons of information | Some information may be irrelevant, and it doesn't provide visual aids (pictures) for ID'ing |
| Identification | The information found here gives a basic idea of anatomy (but pictures are often more helpful for this) | You will have to learn identification very well in order for this to be an effective method for you. |
Recommendations For Group Members
- The team should be prepared for identifying insects (pictures and live/pinned specimens); a lack of practice in either area can result in false identifications.
- The team should be able to use various types of microscopes.
- The team should bring a hand lens to tournaments as well.
Resources
The following guides are highly recommended:
- North America Princeton Field Guide (2023), the official field guide of the Entomology event, on which taxonomic scheme and questions are based on, has great descriptions for orders and somewhat families, also helpful diagrams/dichotomous keys on cover; -note- make sure you know it well as it is large and has 3,700+ pictures and a lot of information
- Audubon Field Guide to Insects and Spiders: the former official field guide of this event, has nice colored pictures and good bug descriptions, good for general insect knowledge; -note- this field guide groups bugs into groups based on their basic appearance rather than their correct phylogenetic groups (not good since the insects in here must be identified according to family and order), is also rather outdated regarding dates and population statistics
- National Wildlife Federation Field Guide to Insects and Spiders & Related Species of North America: contains close-up color photographs with informative description, very up-to-date; -note- has more than 2,000 photos of over 940 species, which may be confusing. However, if you highlight only the necessary insects with the necessary families, the guide becomes much more clear.
- Peterson Field Guides: Insects - shows differences between different insects, has all insects on insect list; -note- contains a lot of information on how to collect and preserve an insect, which may not be useful when preparing for this event.
- Smithsonian Handbooks: Insects - really nice pictures, great for nymphs and larva identification; -note- thin and is best utilized as a supplement (the first two/three field guides are better suited for use during the event)
Good Links
- Bugguide.net
- Official Soinc.org Resources
- mk3966's 2015 SSSS Notes
- 2025 Official Insect List
- NC State University's Entomology Guide
- SciOly ID Bots for Identification Practice
- Rooni’s Entomology Starter Guide














