Insects - Classification

Insects - Classification The classification of animals and plants is based primarily on the physical characteristics and relationships of the animals and plants. The order of classification follows this pattern: kingdom, phylum, class, order, family, genus, and species. The words used in classification are from Latin.

The largest groups are the kingdoms. There are 5 kingdoms for living things on earth. Most animals belong to the kingdom Animalia, and most plants belong to the kingdom Plantae. The other 3 kingdoms are Protista for certain one-celled animals like protozoan, Monera for other simple-celled plants and animals like bacteria and blue-green algae, and Fungi for molds, mushrooms, and yeasts.

The next group called phylum has about 20 phyla for animals and 10 phyla for plants. An example is that all animals with backbones belong to the phylum Chordata.

For animals, the groups called class contains such classes as Mammalia for mammals, Reptilia for reptiles, Aves for birds, and Insecta for insects.

In the next group called order, animals that eat meat are in the order Carnivora and animals that eat insects are in the order Insectivora.

As the groups progress down the pattern of classification, the animals in that group become more and more alike. In animals the group called family contains such families as Felidae for cats and Sciuridae for squirrels. Familiy names always end in "idae".

Genus is the next to last part of the system.

The species is the fundamental unit of the classification system. A species is a group of animals with similar physical characteristics that can and do interbreed and share the same gene pool.

Plants and animals always have a scientific name and usually have a common name as well. For instance, the German cockroach's common name is German cockroach. It's scientific name is Blattella germanica. Names are assigned in two parts--sort of like a person's first and last name. The first part is always capitalized and it refers to the genus of the animal. The second part of the name is not captalized and refers to the species. When you see the scientific name of an animal, you will notice that it is usually italicized because the words are Latin. This system is called binomial nomenclature.

Scientists called taxonomists assign the names to plants and animals. (Taxonomy is the science of identifying, naming, and classifying organisms).

The scientific name of the honeybee is Apis mellifera, and its classification is:

Kindom	Animalia
Phylum	Arthropoda
Class	Insecta
Order	Hymenoptera
Family	Apidae
Genus	Apis
Species	Apis mellifera

Entomologists disagree on how many orders of insects there are. Some charts show as many as 25 different orders. The following 20 are orders that are commonly agreed upon:

The 20 orders of insects are:

Coleoptera - This is the largest order of insects. They have biting mouthparts and hard forewings.
Collembola - Small insects with no wings and long legs used for jumping. Most live in soil.
Dermaptera - Insects with biting mouthparts and long antennae. Most live in rotting plants.
Dictyoptera - Insects that lay their eggs in enclosed capsules called oothecae.
Diptera - Insects with 2 wings and compound eyes. Their mouthparts may be the sucking kind or the sponge-like absorbing kind.
Ephemeroptera - The most primitive winged insect. They have short antennae. Their nymphs live in fast-flowing water.
Hemiptera - Insects with unusual heads. The head has a snout used for piercing and sucking. The wings are usually hard and held flat against the body. The bottom portion of their wings near their body is leathery, and the tip of their wings is membranous.
Homoptera - Insects with piercing/sucking mouthparts. Their wings are membranous from base to tip. These insects feed exclusively on plants.
Hymenoptera - Insects with 4 wings, long legs, and compound eyes. Their mouthparts may be sponging, sucking, or biting.
Isoptera - The name Isoptera comes from the latin iso which means equal because both the front and hind wings of these insects are about the same size.
Lepidoptera - The name comes from lipido which means scale. The wings of these insects are covered by small, overlapping and often colorful scales. Most have sucking mouthparts.
Neuroptera - Insects with large, membranous wings with a dense network of veins.
Odonata - Insects with 2 pairs of wings and biting mouthparts. Most have thin legs and short antennae. Their heads are small, and their large compound eyes nearly cover their heads. Their nymphs live in water.
Orthoptera - These insects have a variety of shapes and characteristics. The one thing that they have in common is that they all move with great agility. Their wings fold over their body when not in use. Some of the females in some of the species in this class are wingless.
Plecoptera - Insects that are flat, with large wings and biting mouthparts. Their larvae live in water.
Protura - Primitive insects with no eyes, antennae, or wings. They live in soil.
Psocoptera - Small insects with long antennae and biting mouthparts.
Siphonaptera - Insects with long legs for jumping and sucking mouth parts.
Thysanura - Insects with soft, flat bodies. They are colorless. They are called bristletails and have short legs but move very rapidly.
Trichoptera - Insects with long antennae and legs. They have hairs on the surface of their wings.

Complete the following activities:

You can make up a sentence or a series of words as a memory device to help you remember something else. It's called a mnemonic sentence. For instance, the sentence----Kittens pounce clumsily on furry, green spiders---can help you remember the pattern for the classification of animals. The first letter of each word is the same as the first letter of each of the words in the pattern for animal classification: kingdom, phylum, class, order, family, genus, and species. Make up your own sentence to help you remember the order.
Write down the 20 orders of insects. Using the following websites find at least one insect that fits in each order. (Example: Orthoptera - cricket).
- The Orders and Selected Families of Insects
- Planet Insect

Teacher Resources

Animal Kingdom Taxonomy - From the University of California Museum of Paleontology. From the frame on the right, you might want to click on "old version" to see the same information with frames.

Living Things - Plant and animal classification.

Author: LINDA MOSBACKER - Email linda.mosbacker@slc.k12.ut.us