pectoral fin

zoology

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Last updated

July 23, 2026

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The pectoral fin is one of the paired fins of a fish, corresponding to the forelimbs of a quadruped. These fins are crucial for stabilization and steering while swimming. In most fish, the pectoral fins, along with the dorsal and caudal fins, help maintain balance and control movement in the water. They articulate with the pectoral girdle, which is located behind the gill region. The evolution of paired fins, including pectoral fins, is thought to have originated from a continuous fold along the sides of ancestral vertebrates.1234

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skeleton
Limbs
The pectoral fin of the elasmobranchs possesses basal cartilages that articulate with the pectoral girdle. They carry a number of radial cartilages consisting of varying numbers of short segments; beyond these are located delicate fin rays.
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The pectoral fin of the elasmobranchs possesses basal cartilages that articulate with the pectoral girdle. They carry a number of radial cartilages consisting of varying numbers of short segments; beyond these are located delicate fin rays.
Read More