Sea horse

A fabulous creature, half horse and half fish, represented in classic mythology as driven by sea dogs or ridden by the Nereids. It is also depicted in heraldry. See Hippocampus.

The walrus.

Any fish of the genus Hippocampus.

small fish with horse-like heads bent sharply downward and curled tails; swim in upright position

either of two large northern marine mammals having ivory tusks and tough hide over thick blubber