Paddle like are used for movement by crustaceans.

Paddle like swimmerets are used for movement by crustaceans.

Swimmerets

Explanation: Swimmerets are normally found on the first five abdominal segments and typically terminate in paired oarlike branches. They function primarily for carrying the eggs in females and are usually adapted for swimming in Crustaceans.

the second type of galaxy is called a barred spiral, which has a thing called a bar straddling the nucleus