New mob for stone beaches

Tiny creatures with spiky shells (resembling clams), would now be found on stony beaches. They would hurt to touch, but not that much. They would thrive in and out of water, and would stick to blocks. This creature could be used in several ways, but mostly as a good source. This allows the stony beaches to have a unique food source. This would be a great feature, as I have explored worlds and found barren stone islands in the middle of the ocean. This could give it some more life.