The Insecta (
insects) are a Class of the large animal Phylum called ARTHROPODA (arthropods) – a name that refers to the jointed limbs.
Classification of Bugs.
| CLASS | CRUSTACEA |
|---|
| MAIN BODY REGIONS | two – cephalothorax* and abdomen (some with head and trunk) |
|---|
| PAIRS OF LEGS | five or more |
|---|
| PAIRS OF ANTENNAE | two |
|---|
| WINGS | absent |
|---|
Insects have a chitinous exoskeleton, a three-part body (head, thorax and abdomen), three pairs of jointed legs, compound eyes and one pair of antennae. Insects are the most diverse group of animals; they include more than a million described species and represent more than half of all known living organisms.
It has long been recognized and documented that insects are the most diverse group of organisms, meaning that the numbers of species of insects are more than any other group. In the world, some 900 thousand different kinds of living insects are known. This representation approximates 80 percent of the world's species.
Arthropod, (phylum Arthropoda), any member of the phylum Arthropoda, the largest phylum in the animal kingdom, which includes such familiar forms as lobsters, crabs, spiders, mites, insects, centipedes, and millipedes. About 84 percent of all known species of animals are members of this phylum.
Features of Insects An insect has six legs. Its body is divided into three parts – Head, Thorax and Abdomen. It has a pair of Antennae to sense and feel the things around. It doesn't have a bone but has a hard covering.
We tend to use the word bug loosely for any very small creature with legs. However, a true bug is defined as belonging to the order Hemiptera. Insects belong to the class Insecta and they are characterized by three-part bodies, usually two pairs of wings, and three pairs of legs, (e.g., bees and mosquitoes).
Taxonomy of insectsInsects in an order can look very different, but they all share important similarities. It is important to be able to identify different species of insects. With the large number of insect species in the world, it is critical to have a system for organising them.
Arthropods can be grouped into several subphyla, with each of these subphyla then divided into different classes. Arthropods are traditionally divided into 5 subphyla: Trilobitomorpha (Trilobites), Chelicerata, Crustacea, Myriapoda, and Hexapoda.
This phylum includes insects like butterflies and beetles, crustaceans like crabs and lobsters, and chelicerates like spiders and scorpions. Arthropods are found in all parts of the world in a wide variety of environments, from the deep sea to the frozen arctic regions.
Most arthropods are scavengers, eating just about anything and everything that settles to the ocean floor. Skeleton shrimp feed detritus, algae or animals. Crabs feed on mollusks they crack with their powerful claws. Their biggest predators are gulls.
They're called crustaceans. Shrimp, crabs, lobsters – they're arthropods, just like crickets. They're also scavengers, which means their diets are as filthy as any bug's.
They are both part of the Phylum Arthropoda. What might surprise you is scorpions are even more closely related to spiders. The anatomy of a scorpion has some similar characteristics to other arthropods, such as lobsters and crabs. They also have similar features to spiders and other arachnids.
Crabs and crayfish are crustaceans, a subdivision of arthropods – the large group of animals without backbones (invertebrates) that includes insects, spiders, mites, scorpions and springtails. Arthropods have jointed legs and a hard outer shell that acts as a skeleton.
Arthropods are
animals that are members of the phylum
Arthropoda.
Some of the common ones include:
- Barnacles.
- Brine shrimp.
- Crabs.
- Crayfish.
- Fish.
- Lice.
- Horseshoe shrimp.
- Krill.
Most arthropods are insects. The phylum also includes spiders, centipedes, and crustaceans. The arthropod body consists of three segments with a hard exoskeleton and jointed appendages. Insects are the only invertebrates that can fly.
Crustaceans (Crustacea /kr?ˈste???/) form a large, diverse arthropod taxon which includes such animals as crabs, lobsters, crayfish, shrimps, prawns, krill, woodlice, and barnacles. Some crustaceans are more closely related to insects and other hexapods than they are to certain other crustaceans.
Terms in this set (39) Give examples of animals found in the subphylum Hexapoda. Butterflies, beetles, flies, ants, bees,wasps etc (insects and entognaths.) Insect body is divided into 3 regions viz., head, thorax and abdomen.
- Answer:
- myriapods > crustaceans > arachnids > insects.
- Explanation:
- Crustaceans have 4 or more pairs of legs ( usually 5 )
- Arachnids have 4 pairs of legs ( ie, 8 legs)
- Insects have 3 pairs of legs.
Insects belong to the class Insecta within the subphylum Hexapoda, the Phylum Arthropoda. Insects are invertebrates with three body parts (head, thorax, and abdomen) and three pairs of jointed legs, and are the most diverse group of animals on this planet.
Entognathous HexapodsCollembola, Protura, and Diplura, the sister taxons of Insecta, are primitive hexapods with mouthparts partly in a depression on the head (i.e., they have 'cheeks'). Wings are absent (they were never present). Development is ametabolous. Malpighian tubules and compound eyes are reduced.
The mandible (from Latin: mandibula or mandĭbŭ-lum, a jaw) of an arthropod is a pair of mouthparts used either for biting or cutting and holding food. Mandibles are present in the extant subphyla Myriapoda (millipedes and others), Crustacea and Hexapoda (insects etc.).
Reproduction. The typical reproductive system of female hexapods features paired ovaries which release eggs into lateral oviducts (Chapman 1998, Stys & Bilinski 1990).
Springtails are closely related to insects – they have six legs and a head, thorax and abdomen – but are not insects because they lack wings and have soft bodies and hidden mouthparts. Springtails are known scientifically as Collembola.
The arachnids (class Arachnida) are an arthropod group that includes spiders, daddy longlegs, scorpions, mites, and ticks as well as lesser-known subgroups.
Arthropods are characterized by a segmented body, a hard exoskeleton, and appendages used for feeding, sensory structures, defense, and locomotion.
All Arthropods share certain characteristics making them unique from other phyla. The muscles of an Arthropod are connected to the inside of the exoskeleton, because the animal lacks an internal skeleton of any type. The exoskeleton is made of a tough substance called chitin (KIE-tin).
Arthropods in Pest ControlHumans use mites to prey on unwanted arthropods on farms or in homes. Other arthropods are used to control weed growth. Cockroaches, spiders, mites, ticks and all other insects considered as carnivorous, prey on smaller species to maintain ecological balance.
Arthropods range in length from about 1 millimeter to 4 meters (about 13 feet). They have a segmented body with a hard exoskeleton. They also have jointed appendages. The body segments are the head, thorax, and abdomen (see Figure below).
Arthropods ingest food through the mouth, which then passes through the pharynx and down the esophagus, similar to many other animals. It eventually reaches the midgut or stomach, where it begins to break down and digest. Waste products pass through the anus of the animal, like many other living organisms.
Arthropods are cold blooded -- which means, their body temperature depends on the temperature of the environment surrounding them. Arthropods are some of the most interesting animals in the world! They fly, they creep, and they crawl.
What makes arthropods so successful? Jointed legs give arthropods more mobility on dry land than mollusks and worms have. Arthropod body segments are more specialized than annelid segments, so arthropods enjoy a greater range of possible activities and behaviors than do segmented worms.
In addition to the exoskeleton and jointed legs, insects have three body divisions (head, thorax, and abdomen), six legs, two antennae, and usually wings.
