Question

Which of the following muscles are directly related to wings?

• A. Dorsal muscle
• B. Axillary muscle
• C. Basalar muscle
• D. Sub-alar muscle

Hint:

Direct wing muscles are attached directly to the axillary sclerites at the wing base. The axillary muscle is responsible for wing folding (flexion).

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Insects fly using a complex system of thoracic muscles.
These muscles are anatomically classified into direct and indirect flight muscles based on whether they attach directly to the wing structures or to the walls of the thoracic skeleton.
Detailed Explanation:
Let us analyze the anatomical relationships of the muscles listed:
- Indirect Flight Muscles: These include the large dorso-longitudinal and dorso-ventral muscles. They do not attach to the wings. Instead, they deform the thoracic box (tergum and sternum) to produce the upward and downward strokes of flight.
- Direct Flight Muscles: These muscles attach directly to the sclerites at the base of the wings.
The basalar and sub-alar muscles are direct flight muscles involved in controlling the pitch and angle of the wing during flight.
- Axillary Muscles: These are direct muscles that attach directly to the axillary sclerites (specifically the 3rd axillary sclerite) at the wing base.
They are responsible for the flexion of the wings, allowing the insect to fold its wings backward over its abdomen when resting.
Because they are directly attached to and control the movements of the individual axillary sclerites of the wing articulation, they are considered directly related to the wing structures.

Step 2: Final Answer:
The axillary muscles are directly attached to the wing base sclerites and are responsible for wing folding.