Question

The larvae of fresh water mussel is called

• A. Nauplius
• B. Glochidium
• C. Megalopa
• D. Zoea

Hint:

Glochidium larvae possess tiny hooks or shells that help them clamp tightly onto the gills or fins of host fishes, which serves as their primary transport mechanism.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Freshwater bivalves (family Unionidae), commonly known as freshwater mussels, have a complex life cycle containing a specialized larval stage that acts as a temporary ectoparasite.

Step 2: Detailed Explanation:
The microscopic larval stage of freshwater mussels is called a glochidium.
Upon release from the adult female mussel, the glochidia must attach to the gills, fins, or skin of a suitable host fish.
They live parasitically on the fish host for several weeks to complete their development and disperse before dropping off to the riverbed as juvenile mussels.
Other larval types like Nauplius and Zoea are typical crustacean larvae, and Megalopa is the post-larval stage of crabs.

Step 3: Final Answer:
The larva of a freshwater mussel is called Glochidium.