What term describes wingless hexapods whose mouthparts are enclosed within the head capsule?

What term describes wingless hexapods whose mouthparts are enclosed within the head capsule?

• A. Entognathous
• B. Exognathous
• C. Hemimetabolous
• D. Holometabolous

Answer: (A)

Mouthparts inside the head capsule indicate a specific arrangement known as entognathous. In entognathous hexapods, the mandibles and other mouthparts are tucked within a hardened pocket of the head, not visible from the outside. This contrasts with exognathous forms, where mouthparts protrude externally from the head. Entognathous groups include primitive, wingless hexapods such as Collembola (springtails), Protura, and Diplura. The other terms describe how the insect develops rather than where mouthparts sit: holometabolous and hemimetabolous refer to complete versus incomplete metamorphosis, and do not address mouthpart placement. So the best description for wingless hexapods with mouthparts enclosed in the head capsule is entognathous.

Mouthparts inside the head capsule indicate a specific arrangement known as entognathous. In entognathous hexapods, the mandibles and other mouthparts are tucked within a hardened pocket of the head, not visible from the outside. This contrasts with exognathous forms, where mouthparts protrude externally from the head. Entognathous groups include primitive, wingless hexapods such as Collembola (springtails), Protura, and Diplura. The other terms describe how the insect develops rather than where mouthparts sit: holometabolous and hemimetabolous refer to complete versus incomplete metamorphosis, and do not address mouthpart placement. So the best description for wingless hexapods with mouthparts enclosed in the head capsule is entognathous.