‘entomon' and `logos'; ‘entomon’



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Figure:Types of mandibles



Maxilla


Situated beneath the mandibles, paired maxillae manipulate food during mastication. Maxillae can have hairs and “teeth” along their inner margins. At the outer margin, the galea is a cupped or scoop-like structure(‡mPbx), which sits over the outer edge of the labium. They also have palps, which are used to sense the characteristics of potential foods.

Labium


The labium is a single structure, although it is formed from two fused secondary maxillae. It can be described as the floor of the mouth. With the maxillae, it assists manipulation of food during mastication.

Hypopharynx


The hypopharynx is a somewhat globular structure, arising from the base of the labium. It assists swallowing (‡Mjv).

Non-chewing mouthparts


Non-chewing mouthparts are modifications of mandibulate mouthparts and are used for 'sucking' up liquids or rasping across the surface of the leaf.
A.Piercing-sucking mouthparts

Piercing and sucking mouthparts are modification of the mandibles and maxillae, which are elongated and modified to form a proboscis for piercing plant tissues. The insect pierces the surface of the plant and sucks out the sap from the host tissues. This action also removes the green chlorophyll from the plant. Examples of insects with piercing-sucking mouthparts include; aphids, leafhoppers, mealy bugs and fleas.


B.Rasping-sucking mouthparts

Rasping and sucking occurs when the insect or mite scrapes off the leaf surface and sucks up the fluids from the top layer of cells. This causes the leaf to turn a silvery colour. Examples of pests with rasping-sucking mouthparts include thrips and mites. The damage caused by thrips and mites looks very similar.







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