Scalloped Hammerhead

Sphyrna lewini

A medium-to-large hammerhead shark with a distinct scalloped head, found in warm coastal waters worldwide.

Zygaena lewinibronze hammerheadkinky-headed hammerheadsouthern hammerhead

Last Updated Mar 9, 2026 · 3 sources

Species Guide

What to know about scalloped hammerheads

A clean field guide focused on habitat, identification, behavior, and conservation context without burying the useful parts.

The scalloped hammerhead (Sphyrna lewini) is a species of hammerhead shark in the family Sphyrnidae. Its most distinguishing feature is the scalloped, hammer-shaped head (cephalofoil), with the eyes and nostrils positioned at the tips of the lateral extensions. It was originally described as Zygaena lewini. This species inhabits warm, temperate, and tropical coastal waters worldwide between about 46°N and 36°S and can be found down to depths of roughly 500 m (1,600 ft). It is reported as the most common of the hammerhead sharks and is smaller than the great and smooth hammerheads.

Identification

How to identify scalloped hammerheads

The visual markers divers can use underwater, plus the species most likely to cause confusion.

Key identification markers

Cephalofoil shape

Distinct scalloped, hammer-shaped head (cephalofoil) that gives the species its common name.

Eyes and nostrils placement

Eyes and nostrils are located at the tips of the lateral extensions of the head.

Relative size

Fairly large for a hammerhead species, but smaller than the great and smooth hammerheads.

Common lookalikes

Great hammerhead (larger)

Larger hammerhead species; scalloped hammerhead is smaller in comparison.

Smooth hammerhead (larger)

Another larger hammerhead species; differs in head shape and size.

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Responsible Encounters

How to dive with scalloped hammerheads

Conservation-minded guidance for divers who want the encounter without adding pressure.

Give scalloped hammerhead space, avoid blocking the animal's path, and follow local site and operator rules for wildlife interactions with saltwater fishes.

Field Notes

Interesting things worth knowing

Useful species context that makes the encounter more meaningful once you are underwater.

Field notes

Name origin

The genus name Sphyrna comes from Greek and translates to "hammer," referring to the head shape.

Taxonomic note

The species was originally described as Zygaena lewini.

Depth range

Reported to occur down to about 500 m (1,600 ft).

Relative commonness

Reported as the most common of all hammerhead species.

FAQ

Frequently asked questions

Clear planning and conservation answers written for search visibility and AI retrieval.

Research Sources

Scalloped Hammerhead information sources

Primary and credible references behind the field-guide and conservation claims on this page.

Sources 3Last Updated

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