Classification: Classifying requires grouping things right into categories based on similar characteristics. Insects, like all living organisms, have the right to be classified follow to their phylogenetic relationships. The classification system offered by scientists involves a hierarchy beginning with a vast category and also ending with a very specific category. In science, us classify organisms follow to kingdom, phylum, class, order, family, genus, and also species.

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Nomenclature: Nomenclature refers to the specify name of organisms. Each organism is provided a surname consisting of 2 words described as the clinical name. The very first word to represent the genus and also the second the species. Scientific names room Latin and are either printed in italics or underlined if handwritten. The scientific name because that the honey bee is Apis mellifera.

Identification of Insects and their Relatives: Insects are component of the phylum of animals called Arthropoda. All arthropods posses an exoskeleton, bi-lateral symmetry, jointed appendages, segmented bodies, and committed appendages. The significant arthropod classes can be be separate by comparing their variety of body regions, legs, and also antennae.


Major exterior Characteristics

1. Exoskeleton comprise chitin

2. Human body bilaterally symmetrical

3. Human body segments group into devoted regions (= tagmata, plural)

4. Jointed appendages

5. These jointed appendages variously committed for feeding, locomotion, sensing

Key to the adult of the common Classes of Arthropoda

1a. Two pairs the antennae (one pair might be reduced, complicated to see);

Number of legs variable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Class Crustacea, go to 2

1b. One pair of antennae or none. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .go come 3

2a. Two distinct body areas (cephlothorax and also abdomen);

Five bag of thoracic legs. . . . . . . . . . . . . . . . . Crayfish, lobsters, shrimp; Order Decapoda

2b. Three distinct body areas (head, thorax, abdomen);

Seven bag of thoracic legs . . . . . . . . . . . . . . Sowbugs, pillbugs, roly-polys; Order Isopoda

3a. No antennae; Two unique body regions (cephlothorax and also abdomen);

Four bag of legs;. . . . . . . . . . . . . . . . . . Spiders, ticks, scorpions, etc; Class Arachnida

3b. One pair that antennae. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

4a. Three distinct body areas (head, thorax, abdomen);

Three bag of thoracic legs. Wings present or absent. . . . . . . . . . . . . . Class Insecta

4b. Two unique body areas (head and also trunk). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

5a. One pair of legs per trunk segment. . . . . . . . . . . . . . . . . . . . . .centipedes; Class Chilopoda

5b. Two pairs that legs every trunk segment. . . . . . . . . . . . . . . . Millipedes; Class Diplopoda


Class Crustacea (crus-ta-ce-uh), the crustaceans. This is a an extremely diverse class. That members screen much variation in the tagmata and also the appendages. Over there are around 30,000 species of Crustacea. Many are aquatic, the majority of which space marine. Crustaceans has lobsters, crabs, crayfish, shrimp, barnacles, and several less familiar forms. One of the latter is the Isopoda, the sowbugs and pillbugs or roly-polys. Most human being will most likely encounter only two orders, the assignment Decapoda and Isopoda.

Order Decapoda (dec-o-po-da). Lobsters, crayfish, crabs, shrimp.

Two tagmata (cephlothorax and also abdomen)

Two bag of antennae (can be complicated to check out both pairs) Five bag of legs on the cephlothorax, the very first pair usually v a big claw

Order Isopoda (eye-so-po-da). Sowbugs, pillbugs, roly-polys.

Three tagmata (head, thorax and also abdomen)

Two pairs of antennae: very first pair is greatly diminished , seldom noticed

Seven bag of legs, one pair on each thoracic segment

Abdomen small, more or much less fused.

Most isopods are marine, living in seaweed and under stones in the water. There are a couple of freshwater forms. The just Crustacea to attack the land space the isopods However, they have actually not severed every ties with the aquatic habitat for they room only discovered in areas of high moisture. This contains places such as leaf litter and also soil and also beneath bark and stones. A few are periodically pests of cultivated plants, however they normally feed on essential debris. Those that have the right to roll into a ball are dubbed pillbugs or roly-polys; those that can not form a ball space the sowbugs.


Class Arachnida (uh-rak-nid-uh), spiders, ticks, mites, scorpions and others. This is a diverse course which belongs to a subphylum the the Arthropoda recognized as the Chelicerata. Chelicerata are characterized as having actually two unique body regions, a cephlothorax and an abdomen. Chelicerates have six bag of appendages, the an initial two pairs being mouthparts and the following four pairs gift legs. They carry out not have antennae.

The very first pair that mouthparts space the chelicerae (sing., chelicera). They room three-segmented and also pincher-like. In spiders, the terminal 3rd segment is often called a fang. The 2nd pair of mouthparts space the six-segmented pedipalps. Lock may appear leg-like (spiders) or claw-like (scorpions). The legs of most Chelicerata have actually seven segments. Compared to insects, whose legs have actually six segments, there is one extra segment, dubbed the patella, in between the third segment (the femur) and also the fourth segment (the tibia). Typical orders of Arachnida include:

Order Araneae (a-ran-e-uh), the spiders.Two tagmata (cephlothorax and also abdomen)

No antennae

Abdomen join to cephlothorax by slim pedicel

Four bag of legs

Mouthparts: One pair chelicerae and one pair of pedipalps

Eyes basic ocelli. Generally eight, periodically fewer

Poison apparatus opens on the fangs of the chelicerae

Silk apparatus constantly present at finish of abdomen, below anus

This is a big order, having around 2500 varieties in north America. Although practically all spiders have actually venom glands, spiders hardly ever bite man. Just a couple of U.S. Types are taken into consideration dangerous. In Nebraska, the black widow and the brown recluse are the only seriously awful spiders

Order Acari (ak-a-ri), the mites and ticks.

Two tagmata (cephlothorax and also abdomen)

No antennae.

Abdomen generally joined come cephlothorax (no pedicel).

Four bag of legs in adults; just three bag at hatching

Ticks and also mites take place just about anywhere pet life is found. They may be terrestrial or aquatic, free-living or parasitic.They might feed on organic debris (beneficial scavengers) or on life plants or animals. Some of the plant feeders are severe pests that crops. Some of the parasitic develops are pests the animals and man. Some space vectors that diseases. A few of the predatory and parasitic mites are thought about beneficial because they feeding on insects or other pests. Over 30,000 types of ticks and mites have actually been described.

Order Scorpiones (scor-pi-on-es), the scorpions.

Two tagmata (cephlothorax and abdomen)

No antennae

No pedicel between cephlothorax and also abdomen

Four bag of legs ~ above cephlothorax

One pair the chelicerae and one pair the long, pincher-like pedipalpsAbdomen with seven vast segments anteriorly, complied with by 5 narrower segments which finish with a large stinger.

Scorpions feed largely on insects and spiders i m sorry they catch with your pedipalps. They may or might not sting your prey. Scorpions carry out not ordinarily assault man, but they will sting if disturbed or cornered. Of the forty-some varieties that occur in the U.S., the sting of many is painful, but not dangerous. One Arizona species, however, is an extremely venomous, and its sting can be fatal.


Class Chilopoda (chi-lo-po-da), the centipedes.


Two tagmata (head and also trunk) One pair the antennae through 14 or much more segments

One pair that legs every trunk segment.

Mouthparts: one pair that mandibles and also two pairs of maxillae

Appendages top top the an initial trunk segment are clawlike toxicity jaws or fangs through which centipedes paralysis their prey.

The class name refers to the lip- favor appearance of the unify bases of this appendages.

Eyes may be existing or absent.

Centipedes room elongate and also flattened. They are usually discovered in somewhat protected places, such together in leaf litter, in the soil, under bark, or in rotten logs. One types is typically found in houses and also other buildings. Centipedes are predatory and also feed top top insects, spiders, and also other little animals.The bigger centipedes have the right to bite humans, however the bite is no serious and also is no much more painful that the sting the a punishment or wasp. The common little centipedes that Nebraska space harmless come man. Overall, centipedes are valuable natural adversaries of insects.


Class Diplopoda (dip-low-po-da), the millipedes.


Two tagmata (head and trunk)

One pair the antennae, usually having seven segments

Two pairs of legs on most trunk segments (30 or more pairs total)

Mouthparts: one pair that mandibles, and also one pair that maxillae

Eyes room usually present

Millipedes room usually cylindrical (sometimes contempt flattened). Other than for the very first three tribe segments, every segment has two bag of short legs. Millipedes are found in damp locations such as the soil, sheet litter, or under logs and also stones. Most millipedes are helpful scavengers that decaying tree material. A few attack life plants and also are sometimes pests. Even fewer are predacious. Millipedes perform not bite man, however many offer off a foul-smelling liquid containing hydrogen cyanide which deserve to be solid enough to kill insects put in a jar through a millipede.


Class Insecta (in- sec-ta), the insects.

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Three tagmata (head, thorax and also abdomen)

One pair that antennae

Three bag of legs

May have actually wings, either one or 2 pairs

Insects are the most abundant life kind now well-known to science. About 1,000,000 species have been described and also named. The is an ext than every the other known pets put together.