What is "pelvic fin"?

The pelvic fin, also known as the ventral fin, is a pair of paired fins found on the underside of a fish's body, specifically in the pelvic region. These fins play a crucial role in the fish's movement and maneuverability, helping to maintain balance and control during swimming. In addition to locomotion, the pelvic fins may also serve reproductive functions, such as assisting in courtship displays or aiding in the transfer of gametes during mating. The shape, size, and structure of the pelvic fins can vary among different fish species, reflecting their adaptations to specific habitats and lifestyles.