Which small hammerhead shark has a shovel-shaped head?

The small hammerhead shark with a shovel-shaped head is the bonnethead.

The bonnethead, Sphyrna tiburo, is the smallest member of the hammerhead genus Sphyrna. It is also called the bonnet shark or shovelhead, names inspired by its broad, smooth, spade-like cephalofoil. Compared with other hammerheads, its head is relatively short and rounded rather than dramatically extended sideways.

Bonnetheads live mainly in warm, shallow coastal waters of the western Atlantic and eastern Pacific. They occur from the Carolinas and the Gulf of Mexico to Brazil, and from southern California to northern Peru. Adults are commonly around 80 to 100 centimetres long, with a recorded maximum of about 150 centimetres.

This species is unusual among sharks in several ways. It is the only shark known to show sexual dimorphism in head shape: adult females usually have a rounded head, while mature males develop a distinct central bulge. It is also one of only two known shark species with documented omnivorous feeding.