Question

Given below are two statements:
Statement (I): Rhodeus deposits eggs on the mantle cavity of freshwater mussel
Statement (II): Careproctus deposits eggs beneath the carapace of crabs
In light of the above statements, choose the most appropriate answer from the options given below.

• A. Both Statement (I) and Statement (II) are correct.
• B. Both Statement (I) and Statement (II) are incorrect.
• C. Statement (I) is correct but Statement (II) is incorrect.
• D. Statement (I) is incorrect but Statement (II) is correct.

Hint:

Both *Rhodeus* (bitterling) and *Careproctus* (snailfish) are notable examples of symbiotic reproductive strategies in ichthyology.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Many fish species have evolved specialized reproductive behaviors to protect their developing eggs from predators, sometimes forming symbiotic associations with invertebrates.

Step 2: Detailed Explanation:
- Statement (I): The bitterling fish (*Rhodeus amarus*) exhibits a highly specialized spawning behavior. The female uses a long, tube-like ovipositor to deposit her eggs directly inside the mantle cavity of a live freshwater unionid mussel. The male then releases sperm near the mussel's incurrent siphon, which draws the sperm in to fertilize the eggs. The developing embryos remain protected inside the mussel's shell until they emerge as free-swimming fry. Thus, Statement (I) is correct.
- Statement (II): Snailfishes of the genus *Careproctus* (such as *Careproctus rastrinus*) use an ovipositor to deposit their eggs beneath the carapace or inside the gill cavity of lithodid crabs (king crabs). The eggs are protected from predators and are continuously aerated by the respiratory water currents generated by the crab. Thus, Statement (II) is correct.

Step 3: Final Answer:
Since both statements describe valid biological adaptations, Option A is correct.