4-H Insect Identification Contest Study Guide for Senior 4-H'ers

Insects are our most abundant form of wildlife. There are more species of insects than there are species of all other animals and plants combined! Your backyard is inhabited by hundreds of species of insects, each with its own unique and interesting biology and habit. Learning about wildlife is rewarding and fun, and the first step in learning about any type of wildlife is identifying what you are looking at.

Learning to identify insects by participating in the 4-H insect identification contest can provide lifelong benefits. Not only will you be able to identify pest insects and understand how to control them, but you will also be better prepared for high school and college biology classes. You will be a better naturalist with a greater understanding and appreciation of the complexity of life and the world in which you live.

The objective of the 4-H insect identification contest is for contestants to learn basic biology of insects and related organisms, to be able to identify insects to the order level, and to be able to identify 100 of the more common insects and arachnids by their common name.

Although this study guide is primarily intended to help 4-H’ers prepare for the insect identification contest, it can also be used by high school science teachers to help teach students about insects and insect identification. High school students who enjoy learning about insects and other wildlife might even want to participate in the 4-H insect identification contest.

Reference materials for this contest include the following publications:

• This study guide (available online or from your local county Extension office)
• Publication 317 4-H Introduction to Entomology (available online or from your local county Extension office)
• Publication 2297 The 4-H Entomology Manual (available online or from your local county Extension office)
• National Wildlife Federation Field Guide to Insects and Spiders and Related Species of North America by Arthur V. Evans (available through libraries and booksellers). This guide includes general information on the biology of insects, spiders, and related arthropods, along with color photographs and basic information for all the insects listed in this study guide. Other field guides and older editions can also be useful, but if you use such guides, be aware that they may use outdated or alternative order classifications.

 

The Contest

The state contest is divided into two parts: specimen identification and a written quiz. Specimens may be pinned, preserved in alcohol, shown in photographs, or shown in visual projections. You will be asked to provide information about the specimen. For example, you may be asked to give either the order or common name of the specimen or to indicate the type of life cycle or type of mouthparts. For the written quiz, you will be asked to provide answers to questions about insect biology and habits. Contestants who know the orders of insects, can identify the insects on the study list by their common name, and are familiar with the information in the 4-H Entomology Manual will do well in the contest.

 

Realize They Are Not All Insects

The Orders of Insects and Arachnids list and the Insect Identification Study List for Seniors both list a few groups or species of land-dwelling creatures that are not insects but do belong to a closely related group of arthropods. These are included because these other land-dwelling arthropods are usually studied by entomologists and because it is important to be able to recognize these creatures and to know they are not insects.

 

Pay Attention to Size

When taking close-up photos of insects, the goal is usually to fill the frame with the specimen in order to show as much detail as possible. This means that, in most field guides, a flea and a bumble bee will appear about the same size. However, any good field guide will also give information about the approximate length of mature specimens, and it is important to make note of this. When reading about an insect you have never seen before, it can be helpful to look at a ruler and visualize just how long the insect is. Of course, seeing or collecting actual specimens is the best way to learn the size of a particular insect species!

Also keep in mind that there can be considerable size variation among mature specimens of many species of insects. For example, some bumble bees can be more than three times larger than other specimens of the same species. Insects do not grow once they reach the adult stage, but the nutrition they receive in the immature stage has a great influence on adult size.

 

Know What You Don’t Know

Contestants should recognize that the 100 insects on the study list represent only a small fraction of the insect species in the state. In the senior division, contestants may be presented with a few specimens of insects that are not on the study list. If this is done, you will be told at the beginning of the contest, and you will be told how many “off list” specimens there are. In this case, you need not correctly identify the specimen. An answer of “not on list” or “I do not know” will be counted as correct. If you happen to know the insect and correctly identify it, your answer will also be counted correct, but you will not get extra credit. For example, if a squash bee or sweat bee is presented and you are asked to supply the common name, you should identify it as “not listed” or “do not know” rather than calling it a honey bee. However, if asked to give the order, type of mouthparts, or type of life cycle for an “off list” specimen, you should be able to do so. The reason for including a few “off list” specimens in the identification contest is that, when identifying insects, it is as important to know what you don’t know as it is to know what you know.

 

Pay Attention to Spelling

Contestants should strive to spell common names and order names correctly. Answers that are badly misspelled will be counted wrong, and spelling may be used to break ties.

It is also helpful to understand why the common names of some insects are written as one word, as in “dragonfly,” while those of other insects are written as two words, as in “house fly.” In general, when an organism really is a member of the group being named, the name is written as two words. If the organism does not really belong to that group, then the name is written as one word. For example, dragonflies, butterflies, and fireflies are not really flies, but house flies and horse flies are. Likewise, hornworms are not really worms, but honey bees really are bees. Also, entomologists use the word “bug” only to refer to a certain subgroup of the order hemiptera: stink bugs, squash bugs, ambush bugs, etc. This is why when lady beetles are referred to as “ladybugs,” it is written as one word. To an entomologist, ladybugs are not true bugs, just as antlions are not really lions, and silverfish are not really fish.

 

The Study List

The study list contains the common names of 100 insects and related arthropods. While some of these names refer to a specific insect, many are names for groups of insects, and there may be dozens, even hundreds, of different species within the group. For example, head louse, monarch butterfly, Colorado potato beetle, and cicada killer are common names for specific insects, but termite, lady beetle, mosquito, and longhorn beetle are names for groups of insects. There are several different species of termites, dozens of different species of lady beetles and mosquitoes, and hundreds of different species of longhorn beetles.

In cases where the listed name represents a group of insects, you are not expected to be able to identify individual species within the groups. However, you should be familiar enough with the characteristics of the listed group to be able to identify a member of the group regardless of which particular species is presented. For example, whether presented with a specimen of a cottonwood borer, a locust borer, or an ivory-marked beetle, the contestant should be able to identify the specimen as a longhorn beetle. This is similar to being able to tell whether a particular desert is a cookie, a pie, or a cake even though you may not know exactly what kind of cookie, pie, or cake it is.

You should be able to identify any specimen to the order level and be able to tell what type of life cycle or mouthparts a specimen has even if it is not on the common names list. For example, if presented with a specimen of an eastern Hercules beetle or any other species of beetle, you should be able to identify it as a member of the order Coleoptera and know that it has chewing mouthparts and a complete life cycle. Likewise, if presented with a caterpillar or any adult moth or butterfly, you should be able to recognize it as a member of the order Lepidoptera.

Refer to National Wildlife Federation Field Guide to Insects and Spiders and Related Species of North America by Arthur V. Evans to become familiar with the listed insects. Most specimens presented in the contest will be species illustrated in this field guide. It will also be helpful to view other photos and illustrations of the listed insects using online sources or other field guides. Collecting or observing actual specimens is an even better way to study!

 

Order

Learning to identify the different orders of insects is the key to learning how to identify insects. Learning the orders is not nearly as difficult as it might first seem. There are only 31 orders, and eight of these (marked with an * in the order table) are so uncommon that you do not need to know them for the contest. See “Orders of Insects and Arachnids” for a list of the orders you need to know.

The names of many orders end in “ptera,” which means wing. Learning the wing characteristics for an order can help you quickly identify most adult insects that belong to that order. For example, moths and butterflies, order Lepidoptera (scale wing), have scales on their wings that rub off on your fingers when you touch them. Beetles, order Coleoptera (sheath winged), have hard, sheath-like front wings. Some order names end in “aptera,” which means “without wings.” Fleas, which have sucking mouthparts and no wings, are in the order Siphonaptera (“Siphon” for tube or pipe and “aptera” for without wings). See the appropriate pages in the 4-H Entomology Manual and in the front of the suggested field guide for more details about insect orders and order names.

Insects within an order have many traits and habits in common, and if you know which order an insect belongs to, you know a lot of other information about that insect. For example, all Diptera have a complete life cycle, and adult flies have sucking or sponging mouthparts. All Hemiptera have a gradual life cycle and have sucking mouthparts as adults and as nymphs. Knowing the orders really is the key to knowing insects! You do not have to memorize what type of mouthparts and life cycle each species of insect has. You just have to know what order it is in and what type of life cycle and mouthparts are characteristic of that order.

 

Host

This column indicates only a few of the more common hosts or food sources of the listed insect. Contestants should recognize that most of the listed insects have many more hosts that are not listed. For example, horn flies feed primarily on cattle but will also feed on horses, goats, and many other animals. For contest purposes, contestants should list the hosts indicated on the study list. Hosts listed for Lepidoptera are for the larval stage.

 

Mouthparts

All insects do not feed in the same way. Some feed on plants by eating the leaves or by boring through fruit, stems, or trunks. Others feed on plants by sucking sap, and still others feed on animals by sucking blood. Moths and butterflies use siphoning mouthparts to suck nectar from flowers through a long thin proboscis. Some flies have sponging/sucking type mouthparts, and some adult insects do not have working mouthparts at all because they do not live very long and do not feed as adults. Knowing what type of mouthparts an insect has can help you know what type of damage it will cause; if the insect is a pest, this information can even help determine which kinds of control will work best.

For purposes of this contest, we will refer to the following five types of mouthparts:

• Chewing (C)—Distinguished by a pair of strong mandibles and a smaller pair of maxillae. Characteristic of beetles, caterpillars, and several other orders.
• Piercing/sucking (P/S)—Distinguished by an elongated, hollow proboscis used to pierce the plant, animal, or insect being fed upon and suck up sap or blood. Characteristic of the Hemiptera and many flies, such as mosquitoes.
• Chewing and sucking (C&S)—Distinguished by having chewing mandibles as well as other mouthparts modified for sucking. Characteristic of bees.
• Sponging (SP)—Distinguished by a hollow proboscis with an enlarged sponge-like structure at the end. Characteristic of house flies and some other flies.
• Siphoning (SIP)—Distinguished by a long, hollow proboscis that is usually rolled up when not in use. Characteristic of adult moths and butterflies.

 

See the information on “How Insects Feed— Mouthparts” in the 4-H Entomology Manual for more information on insect mouthparts and how insects feed.

Be aware that some insects have one type of mouthparts as immatures and a completely different type of mouthparts as adults. For example, moths and butterflies have chewing mouthparts as immatures and siphoning mouthparts as adults. Also be aware that some insects have unusual mouthparts that do not fit any of the above categories. For example, immature lacewings and some predatory beetles have hollow mandibles through which they suck the blood of their insect prey. Head lice have sucking mouthparts, but they are not like the piercing/sucking mouthparts of a bed bug. The sucking mouthparts of spiders, ticks, and mites do not fit any of the above categories exactly.

 

Pest Status or Harmful Stage

The information in this column indicates whether a particular insect or group of insects is considered to be a pest, a beneficial, or neutral (not pests). If the insect is a pest, the harmful stage is indicated. Contestants should recognize that this information is somewhat subjective in nature, and there are often exceptions. For example, cicadas are not usually pests, but large numbers of periodic cicadas can damage fruit trees by causing twigs to break where they insert their eggs. Even though adult females can sting if mishandled, cicada killers are also listed as “not pests” because stings are very rare. Similarly, praying mantids are not listed as being beneficial, even though they are predators of other insects, because they usually prey on insects that are not pests.

 

Contest Preparation

When participating in the contest, answer questions based on the information presented in the study guide—even if you are aware of exceptions to the general information given in the study guide. Biology is not always an exact science; it is often a science of generalities and exceptions to those generalities.