Question

Paleopteran insect orders are
(A) Odonata
(B) Ephemeroptera
(C) Orthoptera
(D) Plecoptera
Choose the correct answer from the options given below:

• A. (A), (B) and (D) only.
• B. (A) and (B) only.
• C. (C) and (D) only.
• D. (B), (C) and (D) only.

Hint:

The "Paleo" in Paleoptera signifies the ancestral condition. If an insect rests with its wings wide open or upright and cannot "tuck them in," it is likely a Paleopteran.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
The sub-division Pterygota (winged insects) is divided into two major groups based on the ability to fold their wings over the abdomen: Paleoptera and Neoptera.
Paleoptera (meaning "ancient wings") includes primitive insects that cannot flex their wings back over their body.
Detailed Explanation:
1. Paleoptera: These insects lack the specialized sclerites (axillary sclerites) and musculature required to fold wings flat over the abdomen at rest.
The wings are held either horizontally out to the sides (like dragonflies) or vertically together above the back (like damselflies and mayflies).
There are only two extant orders in this group:
- Odonata (A): Dragonflies and Damselflies.
- Ephemeroptera (B): Mayflies.
2. Neoptera: These are "new-winged" insects that possess the wing-folding mechanism.
- Orthoptera (C): Grasshoppers and crickets belong to Neoptera.
- Plecoptera (D): Stoneflies belong to Neoptera.
Because the question asks specifically for Paleopteran orders, only (A) and (B) are correct.

Step 2: Final Answer:
The Paleopteran orders are Odonata and Ephemeroptera.