Question

Furcula is present only in:

• A. Mayflies
• B. Springtails
• C. Silverfish
• D. Grasshoppers

Hint:

The furcula is the signature, fork-like jumping organ located on the abdomen of Collembolans (springtails), enabling their characteristic spring-like escape mechanism.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
The furcula is a specialized springing organ found in primitive, wingless hexapods.
It is an evolutionary adaptation that allows rapid escape from predators.

Step 2: Detailed Explanation:
Let us examine the diagnostic structures of the listed groups:
- Mayflies (Ephemeroptera) and Silverfish (Zygentoma) do not possess specialized abdominal springing structures.
- Grasshoppers (Orthoptera) jump using enlarged, muscular hind legs (femora), not abdominal structures.
- Springtails (belonging to the class/order Collembola) are characterized by the presence of a furcula (or furca).
The furcula is a fork-like, tail-like appendage attached to the ventral side of the fourth abdominal segment.
At rest, the furcula is folded forward under the abdomen and held under tension by a clasp-like structure called the retinaculum (on the third abdominal segment).
When threatened, the retinaculum releases the furcula, which snaps downward against the substrate, propelling the springtail forward into the air.
Therefore, the furcula is present only in springtails.

Step 3: Final Answer
The correct option is (B).