Question

Which of the following types of mouthparts do Leptocorisa varicornis have?
A. Cutting and chewing
B. Piercing and sucking
C. Sponging
D. Siphoning

Answer 1

Hint: Insects have a variety of mouthparts that are tailored to different feeding techniques. The mouthparts of all “primitive” insects are designed for grinding, chewing, pinching, or crushing solid food. These mouthparts are called "mandibulate" because they have pronounced chewing mandibles. Mouthparts of insects exist in a variety of shapes and sizes. Chewing and piercing-sucking are the two most common varieties (moths and butterflies have a different, unique form of mouthparts).

Complete explanation:
Option A: Dragonflies, grasshoppers, and beetles are examples of chewing insects. Some insects do not have chewing mouthparts as adults, yet when they feed as larvae, they chew solid food. Adaptations like these can be seen in moths and butterflies.
So, option A is incorrect.
Option B: Slender needle-like stylets pierce the plant cell and suck up plant sap and the fluid inside cells in insects with piercing and sucking mouthparts. Aphids, Leptocorisa varicornis, thrips, mites, and true bugs have piercing and sucking mouthparts, or mouthparts that have been somewhat changed.
So, option B is correct.
Option C: The housefly, for example, feeds itself through sponging. Sponging refers to a mouthpart's ability to absorb liquid food and transport it to the oesophagus. By releasing saliva and rubbing it over the food, the housefly can devour solid food. The sponging mouthpart absorbs the liquid food as the saliva dissolves it.
So, option C is incorrect.
Option D: Insects with syphoning mouthparts do not chew their food; instead, they suck or syphon it through the syphoning mouth parts. Moths and butterflies have mouthparts designed to suck nectar from long-throated flowers.
So, option D is incorrect.

Therefore, Option B is the correct answer.

Note:
Mouthparts are specialised, paired appendages used by insects to obtain and manipulate food. Labrum, mandibles, maxillae, hypopharynx, and labium are the five main structures that make up an insect's mouthparts. Because mandibles, maxillae, and labium grow from metameres during embryonic development, they are regarded as real or appendicular appendages. As a result, these three structures are morphologically equivalent to locomotor appendages. Labrum and hypopharynx, on the other hand, are not real appendages due to their non-metameric origin, however they are termed buccal appendages due to their vital role in feeding.