The scalloped hammerhead (Sphyrna lewini) is a species of hammerhead shark in the family Sphyrnidae. It was originally known as Zygaena lewini. The Greek word sphyrna translates into "hammer" in English, referring to the shape of this shark's head, which is its most distinguishing characteristic.

Sphyrna lewini is a circumglobal shark species native to coastal warm temperate and tropical seas. Its highly migratory nature, slow growth, and lengthy gestation period place this common bycatch species at risk to fishing practices on the high seas, at oceanic congregation sites, and throughout coastal birth zones.

The scalloped hammerhead (Sphyrna lewini) is a globally endangered shark species that has been seriously overfished, primarily for its fins, in targeted and incidental fisheries throughout its range. Great hammerheads (Sphyrna mokarran) and smooth hammerheads (Sphyrna zygaena) resemble scalloped hammerheads and face similar threats.

The scalloped hammerhead (Sphyrna lewini) is a species of hammerhead shark, and part of the family Sphyrnidae. Originally known as Zygaena lewini, its genus name was later changed to its current name. The Greek word sphyrna translates into 'hammer' in English, referring to the shape of this shark's head.

Scalloped hammerhead (Sphyrna lewini) underwater. Photo © Doug Perrine Sphyrna lewini Named for their scallop like cephalophoil (‘hammer head’) these large sharks are open-water hunters. Using their impressive cranium to detect even the most hidden of prey.