A study of insects and their subclasses
In majority of them larval stage is different from the adult and there is a distinct metamorphosis. With even more study, you will be able to assign an insect to an even more precise group.
Types of insects
Google Scholar Kukalova-Peck, J. Having their muscles attached to their exoskeletons is efficient and allows more muscle connections. This arrangement is also seen in the abdomen but only in the first eight segments. Thorax: Three pairs of legs. Some larvae have leg-like appendages on the abdomen. Circulatory system is open type. The abdomen also contains most of the digestive , respiratory , excretory and reproductive internal structures. Abdomen: The gonopore genital opening is at the posterior end of the abdomen. One pair of antennae functions as sensory organs. The dorsal surface is called the tergum or notum to distinguish it from the abdominal terga.
Segmentation The head is enclosed in a hard, heavily sclerotized, unsegmented, exoskeletal head capsule, or epicraniumwhich contains most of the sensing organs, including the antennae, ocellus or eyes, and the mouthparts.
This type of growing is called metamorphosis. Except for the size, all larval stages closely resemble the adults which are wingless.
The nymphs usually have the same feeding habits as the adults. The division of insects into apterygota, exopterygota and endopterygota is mainly based on differences in the type of metamorphosis. Order Isoptera Termites.
There are more than one million living species in the world and many more yet to be discovered. Each segment has four basic regions.
The foregut is lined with a cuticular lining made of chitin and proteins as protection from tough food. This subclass is divided into two superorders or divisions, namely, Exopterygota and Endopterygota. Each segment is dilineated by an intersegmental suture. Characteristics of the Superorder Exopterygota: Insects in this group undergo a simple or incomplete metamorphosis. This break-down process is known as digestion. At least a few insects have nociceptors , cells that detect and transmit signals responsible for the sensation of pain. Scientists believe insects evolved the ability to fly during the Carboniferous period, over million years ago. In molting from egg, via the nymphal stages to an adult, there is a gradual change in the external appearance. Pest species are difficult to control and in spite of about a century of constant efforts, cockroaches, flies and mosquitoes are as abundant as ever.
Order Plecoptera Stone flies and Salmon flies 7. Order Dictyoptera Cockroaches and Mantids 5.
Classification of insects ppt
This arrangement is also seen in the abdomen but only in the first eight segments. If the Apterygota are considered to be indicative of the ground plan for pterygotes, confusion reigns: adult Protura have 12 segments, Collembola have 6. Mouthparts are variously adapted depending on the mode of feeding. Envaginations at the anterior end of the hindgut form the Malpighian tubules, which form the main excretory system of insects. They have 3 pairs of legs and hence sometimes called Hexapoda. Circulatory system is open type. Tiere, 74, 7— Order Plecoptera Stone flies and Salmon flies 7. In prognathous insects, the vertex is not found between the compound eyes, but rather, where the ocelli are normally. One pair of compound eyes and one to three pairs of ocelli sometimes absent may be present. This subclass is divided into two superorders or divisions, namely, Exopterygota and Endopterygota. During this pupal stage big changes take place internally. This type of growing is called metamorphosis. Sometimes the pupa is protected by a cocoon of silk, or it is found in an earthen cell in the soil.
Thorax: Three pairs of legs. There is a big variety in types of mouthparts; biting, sucking, stinging, licking, etc.
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