4-H Insect Identification Study Guide for Junior 4-H'ers

What is it? This is the first question most people ask when they encounter a new kind of animal. Being able to identify an animal is the first step in learning about that animal. Your backyard is home to hundreds of different species of interesting and unusual animals, and most of these animals are insects. Insects affect our lives in many ways. Some insects are pests and some are beneficial, but most insects are neither good nor bad—they are just little animals.

Participating in the 4-H Insect Identification contest will help you learn how to identify insects and learn about the biology and habits of these interesting little animals. For the junior level contest, you only need to learn about 50 of our more common insects, but the skills you acquire in learning about these 50 insects will help you expand your knowledge of insects, as well as other animals and plants, as you move through life.

Reference materials for this contest include the following publications:

• This study guide (available online or from your local county Extension office)
• Mississippi State University Extension 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 through 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 Other field guides and older editions can also be useful, but if you use such guides, be aware that they may use outdated or alternative order classifications.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 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. You must know the information in this study guide, the 4-H Introduction to Entomology, and the indicated sections of the 4-H Entomology Manual (“How Insects Grow and Develop” and “How Insects Feed—Mouthparts”) to do well in the contest.

Spelling Counts

Try 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, but 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” to refer only to a certain subgroup of the order hemiptera: stink bugs, squash bugs, ambush bugs, etc. This is why when a lady beetle is referred to as a “ladybug,” it is written as one word.

The Study Guide

The Orders

There are 31 orders of insects, but most of the insect species in the world belong to one of six orders. If you learn these six orders, you will be able to quickly classify most of the insects you encounter to the order level. Junior contestants will be expected to know only the six orders listed in Table 1. During the specimen identification portion of the contest, you may be presented with an insect and asked to tell which order it belongs to, what type of mouthparts it has, or what its life cycle is. You should be able to recognize members of these six major orders even if the species presented is not one of the 50 species listed in the insect identification study sheet. You should be able to tell whether an insect is a beetle or a butterfly, or a member of one of the other four major orders, even if you have never seen that particular species before.

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. See the appropriate pages in the 4-H Entomology Manual and in the front of the National Wildlife Federation Field Guide for more details about insect orders.

Learning the orders is the key to learning entomology because insects that belong to the same order share many common traits. In particular, they all have the same type of life cycle and the same type of mouthparts. Once you know which order an insect belongs to, you know a lot of other information about that insect. For example, flies are in the order Diptera, and 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 the type of mouthparts and life cycle for each individual species. You just have to know what order it is in and what type of life cycle and mouthparts are characteristic of that order.

Table 1. Major orders of insects.

Study List

The following study list contains the common names of 50 insects and related arthropods. While some of these names refer to a specific insect, most 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, bean leaf 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, you should be able to identify the specimen as a longhorn beetle. This is much like being able to identify a cookie when you see one even though you may not know exactly what kind of cookie it is.

Most specimens presented in the contest will be species that are illustrated in National Wildlife Federation Field Guide to Insects and Spiders and Related Species of North America by Arthur V. Evans. Refer to the field guide to become familiar with the listed insects.

Insect Life Cycles

In the insect world, the process of development is referred to as metamorphosis, meaning change in form or appearance. We may simply refer to this change as the life cycle. There are three basic types of insect life cycles that you will need to know. These are (1) gradual, (2) complete, and (3) ametabolous (without metamorphosis).

Insects with a gradual life cycle go through three stages of development: egg, nymph, and adult. Some insects with this type of development are cockroaches, crickets, stink bugs, and chinch bugs. Many aquatic insects, such as dragonflies, mayflies, caddisflies, and stoneflies have a special type of life cycle that is sometimes referred to as incomplete metamorphosis, but we still refer to it as gradual for the purpose of this study guide and contest.

Insects with a complete life cycle have four stages of development: egg, larva, pupa, and adult. There is a great difference between the immature stages and adults. The larval stage is very active and in many cases is the damaging stage. The pupal stage is the inactive, or resting, stage. Some common insects with this type of development are beetles, butterflies, moths, bees, wasps, and flies.

The third type of development is ametabolous (without metamorphosis). Insects with this type of life cycle never develop wings—the young look just like the adults in every respect. Young insects molt and grow, but their appearance never changes.

See the section on “How Insects Grow and Develop” in the 4-H Entomology Manual for more information on insect metamorphosis.

Insect 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, and, if it is a pest insect, 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:

1. Chewing (C)—Distinguished by a pair of strong mandibles and a smaller pair of maxillae. Characteristic of beetles, caterpillars, and several other orders.
2. Piercing/sucking (P/S)—Distinguished by an elongate, 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.
3. Chewing and sucking (C&S)—Distinguished by having chewing mandibles as well as other mouthparts modified for sucking. Characteristic of bees.
4. Sponging (SP)—Distinguished by a hollow proboscis with an enlarged sponge-like structure at the end. Characteristic of house flies and some other flies.
5. 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.

(i)=the host or type of mouthparts listed are for the immature stage
*In most cases, you will be expected to identify adult specimens, but when the common name is followed by an “(i),” you should be able to identify either the adult or the immature stage.
**Junior contestants will be expected to know only the six orders listed in the table “Major Orders of Insects.” These order names are printed in bold type in the order column.

Contestants may use the following abbreviations (or may use complete spelling):
For mouthparts: C = chewing; P/S = piercing/sucking; C&S = chewing and sucking; SIP = sponging; Sip = Siphoning; sucking = sucking (as in spiders, ticks, and spider mites)
For life cycles: Comp = complete; Grad = gradual; None = none or ametabolus

Publication 2592 (POD-03-18)