Hello aspirant

Caudal fin

The caudal fin is the primary appendage which is used for locomotion in many fishes. The caudal fin is also known as tail fin or a median fin which is usually homocercal or heterocercal. Generally, it is a vertically expanded structure which is located at the caudal end of the body. The base of the caudal fin is known as caudal peduncle with strong swimming muscles.  In general, caudal fin acts like a propeller while the caudal peduncle functions as a motor.

The caudal fin has two lobes such as dorsal epichordal and ventral hypochordal lobe which are supported by the modified last three caudal vertebrae. The shape of the caudal fin may vary in different species from rounded to pointed, notched, emarginated, truncated, etc. It is used to identify the fish species. Generally, fish use it for forwarding propulsion and speed.

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